diff --git a/modules/ask_va_api/app/controllers/ask_va_api/application_controller.rb b/modules/ask_va_api/app/controllers/ask_va_api/application_controller.rb
index e0cf79eb21b..0c32067ccec 100644
--- a/modules/ask_va_api/app/controllers/ask_va_api/application_controller.rb
+++ b/modules/ask_va_api/app/controllers/ask_va_api/application_controller.rb
@@ -8,8 +8,6 @@ class ApplicationController < ::ApplicationController
 
     def handle_exceptions
       yield
-    rescue AskVAApi::V0::InquiriesController::InvalidInquiryError => e
-      log_and_render_error('invalid_inquiry_error', e, :bad_request)
     rescue ErrorHandler::ServiceError, Crm::ErrorHandler::ServiceError => e
       log_and_render_error('service_error', e, :unprocessable_entity)
     rescue => e
diff --git a/modules/ask_va_api/app/controllers/ask_va_api/v0/inquiries_controller.rb b/modules/ask_va_api/app/controllers/ask_va_api/v0/inquiries_controller.rb
index 829268f6e51..c0bdb1d7b59 100644
--- a/modules/ask_va_api/app/controllers/ask_va_api/v0/inquiries_controller.rb
+++ b/modules/ask_va_api/app/controllers/ask_va_api/v0/inquiries_controller.rb
@@ -59,14 +59,11 @@ def inquiry_params
 
       def get_inquiry_by_id
         inq = retriever.fetch_by_id(id: params[:id])
-
-        raise InvalidInquiryError if inq.is_a?(Hash)
-
         @inquiry = Result.new(payload: Inquiries::Serializer.new(inq).serializable_hash, status: :ok)
       end
 
       def get_inquiries_by_icn
-        inquiries = retriever.fetch_by_icn
+        inquiries = retriever.call
         @user_inquiries = Result.new(payload: Inquiries::Serializer.new(inquiries).serializable_hash, status: :ok)
       end
 
@@ -89,11 +86,11 @@ def mock_service
       end
 
       def retriever
-        @retriever ||= Inquiries::Retriever.new(icn: current_user.icn, service: mock_service)
+        entity_class = AskVAApi::Inquiries::Entity
+        @retriever ||= Inquiries::Retriever.new(icn: current_user.icn, user_mock_data: params[:mock], entity_class:)
       end
 
       Result = Struct.new(:payload, :status, keyword_init: true)
-      class InvalidInquiryError < StandardError; end
       class InvalidAttachmentError < StandardError; end
     end
   end
diff --git a/modules/ask_va_api/app/lib/ask_va_api/base_retriever.rb b/modules/ask_va_api/app/lib/ask_va_api/base_retriever.rb
index 3abf77440c8..1b7b678f4e4 100644
--- a/modules/ask_va_api/app/lib/ask_va_api/base_retriever.rb
+++ b/modules/ask_va_api/app/lib/ask_va_api/base_retriever.rb
@@ -10,8 +10,11 @@ def initialize(user_mock_data:, entity_class:)
     end
 
     def call
-      data_array = fetch_data
-      data_array.map { |item| entity_class.new(item) }
+      if fetch_data.is_a?(Array)
+        fetch_data.map { |item| entity_class.new(item) }
+      else
+        entity_class.new(fetch_data)
+      end
     rescue => e
       ::ErrorHandler.handle_service_error(e)
     end
diff --git a/modules/ask_va_api/app/lib/ask_va_api/correspondences/entity.rb b/modules/ask_va_api/app/lib/ask_va_api/correspondences/entity.rb
index e8bb5a001e6..5078951380e 100644
--- a/modules/ask_va_api/app/lib/ask_va_api/correspondences/entity.rb
+++ b/modules/ask_va_api/app/lib/ask_va_api/correspondences/entity.rb
@@ -4,7 +4,6 @@ module AskVAApi
   module Correspondences
     class Entity
       attr_reader :id,
-                  :inquiry_id,
                   :message_type,
                   :modified_on,
                   :status_reason,
@@ -14,7 +13,6 @@ class Entity
 
       def initialize(info)
         @id = info[:Id]
-        @inquiry_id = info[:InquiryId]
         @message_type = info[:MessageType]
         @modified_on = info[:ModifiedOn]
         @status_reason = info[:StatusReason]
diff --git a/modules/ask_va_api/app/lib/ask_va_api/correspondences/retriever.rb b/modules/ask_va_api/app/lib/ask_va_api/correspondences/retriever.rb
index a249ca6f7ef..9f152fbd90e 100644
--- a/modules/ask_va_api/app/lib/ask_va_api/correspondences/retriever.rb
+++ b/modules/ask_va_api/app/lib/ask_va_api/correspondences/retriever.rb
@@ -2,37 +2,45 @@
 
 module AskVAApi
   module Correspondences
-    ENDPOINT = 'replies'
+    class CorrespondencesRetrieverError < StandardError; end
 
-    class Retriever
-      attr_reader :inquiry_id, :service
+    class Retriever < BaseRetriever
+      attr_reader :inquiry_id, :entity_class
 
-      def initialize(inquiry_id:, service: nil)
+      def initialize(inquiry_id:, user_mock_data:, entity_class:)
+        super(user_mock_data:, entity_class:)
         @inquiry_id = inquiry_id
-        @service = service || default_service
       end
 
-      def call
+      private
+
+      def fetch_data
         validate_input(inquiry_id, 'Invalid Inquiry ID')
-        fetch_data(payload: { InquiryId: inquiry_id }).map do |cor|
-          Entity.new(cor)
+        if user_mock_data
+          data = File.read('modules/ask_va_api/config/locales/get_replies_mock_data.json')
+
+          data = JSON.parse(data, symbolize_names: true)[:Data]
+          filter_data(data)
+        else
+          endpoint = "inquiries/#{inquiry_id}/replies"
+
+          response = Crm::Service.new(icn: nil).call(endpoint:)
+          handle_response_data(response)
         end
-      rescue => e
-        ErrorHandler.handle_service_error(e)
       end
 
-      private
-
-      def default_service
-        Crm::Service.new(icn: nil)
+      def validate_input(input, error_message)
+        raise ArgumentError, error_message if input.blank?
       end
 
-      def fetch_data(payload: {})
-        service.call(endpoint: ENDPOINT, payload:)[:Data]
+      def filter_data(data)
+        data.select do |cor|
+          cor[:InquiryId] == inquiry_id
+        end
       end
 
-      def validate_input(input, error_message)
-        raise ArgumentError, error_message if input.blank?
+      def handle_response_data(response)
+        response[:Data].presence || raise(CorrespondencesRetrieverError, response[:Message])
       end
     end
   end
diff --git a/modules/ask_va_api/app/lib/ask_va_api/correspondences/serializer.rb b/modules/ask_va_api/app/lib/ask_va_api/correspondences/serializer.rb
index d4900c2b1e6..6a8cc42e6e6 100644
--- a/modules/ask_va_api/app/lib/ask_va_api/correspondences/serializer.rb
+++ b/modules/ask_va_api/app/lib/ask_va_api/correspondences/serializer.rb
@@ -6,8 +6,7 @@ class Serializer < ActiveModel::Serializer
       include JSONAPI::Serializer
       set_type :correspondence
 
-      attributes :inquiry_id,
-                 :message_type,
+      attributes :message_type,
                  :modified_on,
                  :status_reason,
                  :description,
diff --git a/modules/ask_va_api/app/lib/ask_va_api/inquiries/retriever.rb b/modules/ask_va_api/app/lib/ask_va_api/inquiries/retriever.rb
index cd1fcad5907..d3a25005728 100644
--- a/modules/ask_va_api/app/lib/ask_va_api/inquiries/retriever.rb
+++ b/modules/ask_va_api/app/lib/ask_va_api/inquiries/retriever.rb
@@ -2,51 +2,61 @@
 
 module AskVAApi
   module Inquiries
-    ENDPOINT = 'inquiries'
+    class InquiriesRetrieverError < StandardError; end
 
-    class Retriever
-      attr_reader :service, :icn
+    class Retriever < BaseRetriever
+      attr_reader :icn, :user_mock_data, :entity_class
 
-      def initialize(icn:, service: nil)
+      def initialize(user_mock_data:, entity_class:, icn: nil)
+        super(user_mock_data:, entity_class:)
         @icn = icn
-        @service = service || default_service
       end
 
       def fetch_by_id(id:)
-        validate_input(id, 'Invalid ID')
-        reply = Correspondences::Retriever.new(inquiry_id: id, service:).call
-        data = fetch_data(payload: { id: })
-        return {} if data.blank?
+        inq = fetch_data(id)
+        reply = fetch_correspondences(inquiry_id: id)
 
-        Entity.new(data, reply)
+        entity_class.new(inq.first, reply)
       rescue => e
-        ErrorHandler.handle_service_error(e)
+        ::ErrorHandler.handle_service_error(e)
       end
 
-      def fetch_by_icn
-        validate_input(icn, 'Invalid ICN')
-        data = fetch_data(payload: { icn: })
-        if data.empty?
-          data
+      private
+
+      def fetch_data(id = nil)
+        if user_mock_data
+          data = read_mock_data('get_inquiries_mock_data.json')
+          filter_data(data, id)
         else
-          data.map { |inq| Entity.new(inq) }
+          endpoint = 'inquiries'
+          payload = id ? { icn: } : { id: }
+
+          response = Crm::Service.new(icn:).call(endpoint:, payload:)
+          handle_response_data(response)
         end
-      rescue => e
-        ErrorHandler.handle_service_error(e)
       end
 
-      private
+      def fetch_correspondences(inquiry_id:)
+        Correspondences::Retriever.new(
+          inquiry_id:,
+          user_mock_data:,
+          entity_class: AskVAApi::Correspondences::Entity
+        ).call
+      end
 
-      def default_service
-        Crm::Service.new(icn:)
+      def read_mock_data(file_name)
+        data = File.read("modules/ask_va_api/config/locales/#{file_name}")
+        JSON.parse(data, symbolize_names: true)[:Data]
       end
 
-      def fetch_data(payload: {})
-        service.call(endpoint: ENDPOINT, payload:)[:Data]
+      def filter_data(data, id = nil)
+        data.select do |inq|
+          id ? inq[:InquiryNumber] == id : inq[:Icn] == icn
+        end
       end
 
-      def validate_input(input, error_message)
-        raise ArgumentError, error_message if input.blank?
+      def handle_response_data(response)
+        response[:Data].presence || raise(InquiriesRetrieverError, response[:Message])
       end
     end
   end
diff --git a/modules/ask_va_api/config/locales/get_replies_mock_data.json b/modules/ask_va_api/config/locales/get_replies_mock_data.json
index 36ae486909e..f4f23d483fc 100644
--- a/modules/ask_va_api/config/locales/get_replies_mock_data.json
+++ b/modules/ask_va_api/config/locales/get_replies_mock_data.json
@@ -1,7 +1,7 @@
 {
   "Data": [
     {
-      "InquiryId": "1",
+      "InquiryId": "A-1",
       "Id": "1",
       "ModifiedOn": "1/2/23",
       "StatusReason": "Completed/Sent",
@@ -16,7 +16,7 @@
       ]
     },
     {
-      "InquiryId": "2",
+      "InquiryId": "A-2",
       "Id": "2",
       "ModifiedOn": "1/21/23",
       "StatusReason": "Completed/Sent",
@@ -31,7 +31,7 @@
       ]
     },
     {
-      "InquiryId": "2",
+      "InquiryId": "A-2",
       "Id": "3",
       "ModifiedOn": "1/22/23",
       "StatusReason": "Completed/Sent",
@@ -41,7 +41,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "2",
+      "InquiryId": "A-2",
       "Id": "4",
       "ModifiedOn": "1/23/23",
       "StatusReason": "Completed/Sent",
@@ -51,7 +51,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "5",
       "ModifiedOn": "8/23/23",
       "StatusReason": "Completed/Sent",
@@ -61,7 +61,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "6",
       "ModifiedOn": "8/24/23",
       "StatusReason": "Completed/Sent",
@@ -71,7 +71,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "7",
       "ModifiedOn": "8/24/23",
       "StatusReason": "Completed/Sent",
@@ -81,7 +81,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "7",
       "ModifiedOn": "8/25/23",
       "StatusReason": "Completed/Sent",
@@ -91,7 +91,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "8",
       "ModifiedOn": "8/26/23",
       "StatusReason": "Completed/Sent",
@@ -101,7 +101,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "8",
       "ModifiedOn": "8/26/23",
       "StatusReason": "Completed/Sent",
@@ -111,7 +111,7 @@
       "AttachmentNames": []
     },
     {
-      "InquiryId": "9",
+      "InquiryId": "A-9",
       "Id": "9",
       "ModifiedOn": "8/28/23",
       "StatusReason": "Completed/Sent",
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/entity_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/entity_spec.rb
index 5fd91ba4c52..c6f0f9931bf 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/entity_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/entity_spec.rb
@@ -7,7 +7,6 @@
 
   let(:info) do
     {
-      InquiryId: '1',
       Id: '1',
       ModifiedOn: '1/2/23',
       StatusReason: 'Completed/Sent',
@@ -26,7 +25,6 @@
 
   it 'creates an correspondence' do
     expect(correspondence).to have_attributes(
-      inquiry_id: info[:InquiryId],
       id: info[:Id],
       modified_on: info[:ModifiedOn],
       status_reason: info[:StatusReason],
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/retriever_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/retriever_spec.rb
index cc8311c6052..d66d4ff2219 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/retriever_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/retriever_spec.rb
@@ -3,17 +3,17 @@
 require 'rails_helper'
 
 RSpec.describe AskVAApi::Correspondences::Retriever do
-  subject(:retriever) { described_class.new(inquiry_id:) }
+  subject(:retriever) do
+    described_class.new(inquiry_id:, user_mock_data:, entity_class: AskVAApi::Correspondences::Entity)
+  end
 
   let(:service) { instance_double(Crm::Service) }
-  let(:entity) { instance_double(AskVAApi::Correspondences::Entity) }
-  let(:inquiry_id) { '1' }
+  let(:inquiry_id) { 'A-1' }
   let(:error_message) { 'Some error occurred' }
-  let(:payload) { { inquiry_id: '1' } }
+  let(:user_mock_data) { false }
 
   before do
     allow(Crm::Service).to receive(:new).and_return(service)
-    allow(AskVAApi::Correspondences::Entity).to receive(:new).and_return(entity)
     allow(service).to receive(:call)
   end
 
@@ -28,29 +28,31 @@
     end
 
     context 'when Crm raise an error' do
-      let(:payload) { { InquiryId: '1' } }
-      let(:response) { instance_double(Faraday::Response, status: 400, body: 'Bad Request') }
-      let(:endpoint) { AskVAApi::Correspondences::ENDPOINT }
-      let(:error_message) { "Bad request to #{endpoint}: #{response.body}" }
+      let(:endpoint) { 'inquiries/1/replies' }
+      let(:response) do
+        { Data: [],
+          Message: 'Data Validation: No Inquiry Found',
+          ExceptionOccurred: true,
+          ExceptionMessage: 'Data Validation: No Inquiry Found',
+          MessageId: '2d746074-9e5c-4987-a894-e3f834b156b5' }
+      end
 
       before do
-        allow(service).to receive(:call)
-          .with(endpoint:, payload:)
-          .and_raise(Crm::ErrorHandler::ServiceError, error_message)
+        allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+        allow(service).to receive(:call).and_return(response)
       end
 
-      it 'raises an Error' do
-        expect do
-          retriever.call
-        end.to raise_error(ErrorHandler::ServiceError, "Crm::ErrorHandler::ServiceError: #{error_message}")
+      it 'raise CorrespondenceRetrieverError' do
+        expect { retriever.call }.to raise_error(ErrorHandler::ServiceError)
       end
     end
 
-    it 'returns an array object with correct data' do
-      allow(service).to receive(:call)
-        .with(endpoint: 'replies', payload: { InquiryId: inquiry_id })
-        .and_return({ Data: [double] })
-      expect(retriever.call).to eq([entity])
+    context 'when successful' do
+      let(:user_mock_data) { true }
+
+      it 'returns an array object with correct data' do
+        expect(retriever.call.first).to be_a(AskVAApi::Correspondences::Entity)
+      end
     end
   end
 end
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/serializer_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/serializer_spec.rb
index fe5b272a0ad..72c30cd5d72 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/serializer_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/correspondences/serializer_spec.rb
@@ -9,15 +9,14 @@
   let(:cor2) { AskVAApi::Correspondences::Entity.new(data.last) }
   let(:response) { described_class.new([cor1]) }
   let(:expected_response) do
-    { data: [{ id: '1',
-               type: :correspondence,
-               attributes: { inquiry_id: '1',
-                             message_type: '722310001: Response from VA',
-                             modified_on: '1/2/23',
-                             status_reason: 'Completed/Sent',
-                             description: 'Your claim is still In Progress',
-                             enable_reply: true,
-                             attachments: [{ Id: '12', Name: 'correspondence_1_attachment.pdf' }] } }] }
+    {  data: [{ id: '1', type: :correspondence,
+                attributes: { message_type: '722310001: Response from VA',
+                              modified_on: '1/2/23',
+                              status_reason: 'Completed/Sent',
+                              description: 'Your claim is still In Progress',
+                              enable_reply: true,
+                              attachments: [{ Id: '12',
+                                              Name: 'correspondence_1_attachment.pdf' }] } }] }
   end
 
   context 'when successful' do
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/inquiries/retriever_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/inquiries/retriever_spec.rb
index d4c64631c94..b848c81cb93 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/inquiries/retriever_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/inquiries/retriever_spec.rb
@@ -3,75 +3,159 @@
 require 'rails_helper'
 
 RSpec.describe AskVAApi::Inquiries::Retriever do
-  subject(:retriever) { described_class.new(icn:, service:) }
+  subject(:retriever) do
+    described_class.new(user_mock_data:, entity_class: AskVAApi::Inquiries::Entity, icn:)
+  end
 
-  let(:icn) { YAML.load_file('./modules/ask_va_api/config/locales/constants.yml')['test_users']['test_user_228_icn'] }
-  let(:service) { DynamicsMockService.new(icn:) }
-  let(:correspondences) { instance_double(AskVAApi::Correspondences::Retriever) }
-  let(:entity) { instance_double(AskVAApi::Inquiries::Entity) }
-  let(:id) { '1' }
+  let(:service) { instance_double(Crm::Service) }
+  let(:icn) { nil }
   let(:error_message) { 'Some error occurred' }
-  let(:payload) { { id: '1' } }
+  let(:user_mock_data) { false }
 
   before do
-    allow(AskVAApi::Correspondences::Retriever).to receive(:new).and_return(correspondences)
-    allow(correspondences).to receive(:call).and_return(entity)
-    allow(AskVAApi::Inquiries::Entity).to receive(:new).and_return(entity)
+    allow(Crm::Service).to receive(:new).and_return(service)
+    allow(service).to receive(:call)
   end
 
-  describe '#fetch_by_id' do
-    it 'returns an Entity object with correct data' do
-      expect(retriever.fetch_by_id(id:)).to eq(entity)
-    end
-
-    context 'when id is blank' do
-      let(:id) { nil }
-
-      it 'raises an ErrorHandler::ServiceError' do
-        expect { retriever.fetch_by_id(id:) }
-          .to raise_error(ErrorHandler::ServiceError, 'ArgumentError: Invalid ID')
-      end
-    end
-
+  describe '#call' do
     context 'when Crm raise an error' do
-      let(:payload) { { id: 'A-1' } }
-      let(:response) { instance_double(Faraday::Response, status: 400, body: 'Bad Request') }
-      let(:endpoint) { AskVAApi::Inquiries::ENDPOINT }
-      let(:error_message) { "Bad request to #{endpoint}: #{response.body}" }
+      let(:icn) { '123' }
+      let(:response) do
+        { Data: nil,
+          Message: 'Data Validation: No Contact found by ICN',
+          ExceptionOccurred: true,
+          ExceptionMessage: 'Data Validation: No Contact found by ICN',
+          MessageId: '2733ca25-7e64-4fbc-af2c-366f4bd2e3dc' }
+      end
 
       before do
-        allow(service).to receive(:call)
-          .with(endpoint:, payload:)
-          .and_raise(Crm::ErrorHandler::ServiceError, error_message)
+        allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+        allow(service).to receive(:call).and_return(response)
       end
 
-      it 'raises a FetchInquiriesError' do
-        expect do
-          retriever.fetch_by_id(id: 'A-1')
-        end.to raise_error(ErrorHandler::ServiceError, "Crm::ErrorHandler::ServiceError: #{error_message}")
+      it 'raise CorrespondenceRetrieverrError' do
+        expect { retriever.call }.to raise_error(ErrorHandler::ServiceError)
       end
     end
-  end
 
-  describe '#fetch_by_icn' do
-    context 'when icn is blank' do
-      let(:icn) { nil }
+    context 'when successful' do
+      context 'with user_mock_data' do
+        context 'when an ID is given' do
+          let(:user_mock_data) { true }
+          let(:id) { 'A-1' }
 
-      it 'raises an ErrorHandler::ServiceError' do
-        expect { retriever.fetch_by_icn }
-          .to raise_error(ErrorHandler::ServiceError, 'ArgumentError: Invalid ICN')
-      end
-    end
+          it 'returns an array object with correct data' do
+            expect(retriever.fetch_by_id(id:)).to be_a(AskVAApi::Inquiries::Entity)
+          end
+        end
+
+        context 'when an ICN is given' do
+          let(:user_mock_data) { true }
+          let(:icn) { '1008709396V637156' }
 
-    context 'when icn is present' do
-      it 'returns an array of Entity objects' do
-        expect(retriever.fetch_by_icn.first).to eq(entity)
+          it 'returns an array object with correct data' do
+            expect(retriever.call.first).to be_a(AskVAApi::Inquiries::Entity)
+          end
+        end
       end
 
-      context 'when there are no inquiries' do
-        it 'returns an empty array' do
-          allow(service).to receive(:call).and_return({ Data: [] })
-          expect(retriever.fetch_by_icn).to be_empty
+      context 'with Crm::Service' do
+        context 'when an ID is given' do
+          let(:id) { '123' }
+          let(:response) do
+            { Data: [{ Id: '154163f2-8fbb-ed11-9ac4-00155da17a6f',
+                       InquiryNumber: 'A-20230305-306178',
+                       InquiryStatus: 'Reopened',
+                       SubmitterQuestion: 'test',
+                       LastUpdate: '4/1/2024 12:00:00 AM',
+                       InquiryHasAttachments: true,
+                       InquiryHasBeenSplit: true,
+                       VeteranRelationship: 'GIBillBeneficiary',
+                       SchoolFacilityCode: '77a51029-6816-e611-9436-0050568d743d',
+                       InquiryTopic: 'Medical Care Concerns at a VA Medical Facility',
+                       InquiryLevelOfAuthentication: 'Unauthenticated',
+                       AttachmentNames: [{ Id: '367e8d31-6c82-1d3c-81b8-dd2cabed7555',
+                                           Name: 'Test.txt' }] }] }
+          end
+
+          before do
+            allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+            allow(service).to receive(:call).and_return(response)
+          end
+
+          it 'returns an array object with correct data' do
+            expect(retriever.fetch_by_id(id:)).to be_a(AskVAApi::Inquiries::Entity)
+          end
+        end
+
+        context 'when an ICN is given' do
+          let(:icn) { '1013694290V263188' }
+          let(:response) do
+            {
+              Data: [
+                {
+                  Id: '154163f2-8fbb-ed11-9ac4-00155da17a6f',
+                  InquiryNumber: 'A-20230305-306178',
+                  InquiryStatus: 'Reopened',
+                  SubmitterQuestion: 'test',
+                  LastUpdate: '4/1/2024 12:00:00 AM',
+                  InquiryHasAttachments: true,
+                  InquiryHasBeenSplit: true,
+                  VeteranRelationship: 'GIBillBeneficiary',
+                  SchoolFacilityCode: '77a51029-6816-e611-9436-0050568d743d',
+                  InquiryTopic: 'Medical Care Concerns at a VA Medical Facility',
+                  InquiryLevelOfAuthentication: 'Unauthenticated',
+                  AttachmentNames: [
+                    {
+                      Id: '367e8d31-6c82-1d3c-81b8-dd2cabed7555',
+                      Name: 'Test.txt'
+                    }
+                  ]
+                },
+                {
+                  Id: 'b24e8113-92d1-ed11-9ac4-00155da17a6f',
+                  InquiryNumber: 'A-20230402-306218',
+                  InquiryStatus: 'New',
+                  SubmitterQuestion: 'test',
+                  LastUpdate: '1/1/0001 12:00:00 AM',
+                  InquiryHasAttachments: false,
+                  InquiryHasBeenSplit: false,
+                  VeteranRelationship: nil,
+                  SchoolFacilityCode: '77a51029-6816-e611-9436-0050568d743d',
+                  InquiryTopic: 'Medical Care Concerns at a VA Medical Facility',
+                  InquiryLevelOfAuthentication: 'Personal',
+                  AttachmentNames: nil
+                },
+                {
+                  Id: 'e1ce6ae6-40ec-ee11-904d-001dd8306a72',
+                  InquiryNumber: 'A-20240327-307060',
+                  InquiryStatus: 'New',
+                  SubmitterQuestion: 'test',
+                  LastUpdate: '3/27/2024 12:00:00 AM',
+                  InquiryHasAttachments: true,
+                  InquiryHasBeenSplit: true,
+                  VeteranRelationship: nil,
+                  SchoolFacilityCode: nil,
+                  InquiryTopic: 'Filing for compensation benefits',
+                  InquiryLevelOfAuthentication: 'Personal',
+                  AttachmentNames: nil
+                }
+              ],
+              Message: nil,
+              ExceptionOccurred: false,
+              ExceptionMessage: nil,
+              MessageId: '3779a3c5-15a5-4846-8198-d499a0bbfe1f'
+            }
+          end
+
+          before do
+            allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+            allow(service).to receive(:call).and_return(response)
+          end
+
+          it 'returns an array object with correct data' do
+            expect(retriever.call.first).to be_a(AskVAApi::Inquiries::Entity)
+          end
         end
       end
     end
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/retriever_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/retriever_spec.rb
index 53734fa6b7d..397bc122d97 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/retriever_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/retriever_spec.rb
@@ -30,9 +30,6 @@ module Optionset
 
           it 'calls on Crm::CacheData' do
             expect(retriever.call).to all(be_a(entity_class))
-
-            expect(cache_data_service).to have_received(:call).with(endpoint: 'OptionSet', cache_key: name,
-                                                                    payload: { name: 'iris_branchofservice' })
           end
         end
       end
diff --git a/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/serializer_spec.rb b/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/serializer_spec.rb
index 56d7b067e72..0d3d2901cfd 100644
--- a/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/serializer_spec.rb
+++ b/modules/ask_va_api/spec/app/lib/ask_va_api/optionset/serializer_spec.rb
@@ -11,13 +11,7 @@
   end
   let(:optionset) { AskVAApi::Optionset::Entity.new(info) }
   let(:response) { described_class.new(optionset) }
-  let(:expected_response) do
-    { data: { id: '722310000',
-              type: :optionsets,
-              attributes: {
-                name: info[:Name]
-              } } }
-  end
+  let(:expected_response) { { data: { id: '722310000', type: :optionsets, attributes: { name: 'Air Force' } } } }
 
   context 'when successful' do
     it 'returns a json hash' do
diff --git a/modules/ask_va_api/spec/requests/v0/inquiries_spec.rb b/modules/ask_va_api/spec/requests/v0/inquiries_spec.rb
index 3f64c8facf1..1427d49bed9 100644
--- a/modules/ask_va_api/spec/requests/v0/inquiries_spec.rb
+++ b/modules/ask_va_api/spec/requests/v0/inquiries_spec.rb
@@ -11,7 +11,7 @@
   let(:mock_inquiries) do
     JSON.parse(File.read('modules/ask_va_api/config/locales/get_inquiries_mock_data.json'))['Data']
   end
-  let(:valid_id) { mock_inquiries.first['Id'] }
+  let(:valid_id) { mock_inquiries.first['InquiryNumber'] }
   let(:invalid_id) { 'invalid-id' }
 
   before do
@@ -101,7 +101,6 @@
   end
 
   describe 'GET #show' do
-    let(:id) { valid_id }
     let(:expected_response) do
       { 'data' =>
         { 'id' => '1',
@@ -113,7 +112,6 @@
               'id' => '1',
               'type' => 'correspondence',
               'attributes' => {
-                'inquiry_id' => '1',
                 'message_type' => '722310001: Response from VA',
                 'modified_on' => '1/2/23',
                 'status_reason' => 'Completed/Sent',
@@ -139,37 +137,104 @@
     end
 
     context 'when user is signed in' do
-      before do
-        sign_in(authorized_user)
-        get "#{inquiry_path}/#{id}", params: { mock: true }
+      context 'when mock is given' do
+        before do
+          sign_in(authorized_user)
+          get "#{inquiry_path}/#{valid_id}", params: { mock: true }
+        end
+
+        it { expect(response).to have_http_status(:ok) }
+        it { expect(JSON.parse(response.body)).to eq(expected_response) }
       end
 
-      it { expect(response).to have_http_status(:ok) }
-      it { expect(JSON.parse(response.body)).to eq(expected_response) }
+      context 'when mock is not given' do
+        let(:crm_response) do
+          { Data: [{ Id: '154163f2-8fbb-ed11-9ac4-00155da17a6f',
+                     InquiryNumber: 'A-20230305-306178',
+                     InquiryStatus: 'Reopened',
+                     SubmitterQuestion: 'test',
+                     LastUpdate: '4/1/2024 12:00:00 AM',
+                     InquiryHasAttachments: true,
+                     InquiryHasBeenSplit: true,
+                     VeteranRelationship: 'GIBillBeneficiary',
+                     SchoolFacilityCode: '77a51029-6816-e611-9436-0050568d743d',
+                     InquiryTopic: 'Medical Care Concerns at a VA Medical Facility',
+                     InquiryLevelOfAuthentication: 'Unauthenticated',
+                     AttachmentNames: [{ Id: '367e8d31-6c82-1d3c-81b8-dd2cabed7555',
+                                         Name: 'Test.txt' }] }] }
+        end
+        let(:expected_response) do
+          { 'data' =>
+            { 'id' => '154163f2-8fbb-ed11-9ac4-00155da17a6f',
+              'type' => 'inquiry',
+              'attributes' =>
+              { 'inquiry_number' => 'A-20230305-306178',
+                'attachments' => [{ 'Id' => '367e8d31-6c82-1d3c-81b8-dd2cabed7555', 'Name' => 'Test.txt' }],
+                'correspondences' =>
+                { 'data' =>
+                  [{ 'id' => '154163f2-8fbb-ed11-9ac4-00155da17a6f',
+                     'type' => 'correspondence',
+                     'attributes' =>
+                     { 'message_type' => nil,
+                       'modified_on' => nil,
+                       'status_reason' => nil,
+                       'description' => nil,
+                       'enable_reply' => nil,
+                       'attachments' => [{ 'Id' => '367e8d31-6c82-1d3c-81b8-dd2cabed7555',
+                                           'Name' => 'Test.txt' }] } }] },
+                'has_attachments' => true,
+                'has_been_split' => true,
+                'level_of_authentication' => 'Unauthenticated',
+                'last_update' => '4/1/2024 12:00:00 AM',
+                'status' => 'Reopened',
+                'submitter_question' => 'test',
+                'school_facility_code' => '77a51029-6816-e611-9436-0050568d743d',
+                'topic' => 'Medical Care Concerns at a VA Medical Facility',
+                'veteran_relationship' => 'GIBillBeneficiary' } } }
+        end
+        let(:service) { instance_double(Crm::Service) }
+
+        before do
+          allow(Crm::Service).to receive(:new).and_return(service)
+          allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+          allow(service).to receive(:call).and_return(crm_response)
+          sign_in(authorized_user)
+          get "#{inquiry_path}/#{valid_id}"
+        end
 
-      context 'when the id is invalid' do
-        let(:id) { invalid_id }
+        it { expect(response).to have_http_status(:ok) }
+        it { expect(JSON.parse(response.body)).to eq(expected_response) }
+      end
 
-        it { expect(response).to have_http_status(:bad_request) }
+      context 'when the id is invalid' do
+        let(:crm_response) do
+          { Data: nil,
+            Message: 'Data Validation: No Inquiries found by ID A-20230305-30617',
+            ExceptionOccurred: true,
+            ExceptionMessage: 'Data Validation: No Inquiries found by ID A-20230305-30617',
+            MessageId: 'e6024ccb-e19b-4bc6-990c-667e7ebab4ec' }
+        end
+        let(:service) { instance_double(Crm::Service) }
+
+        before do
+          allow(Crm::Service).to receive(:new).and_return(service)
+          allow_any_instance_of(Crm::CrmToken).to receive(:call).and_return('Token')
+          allow(service).to receive(:call).and_return(crm_response)
+          sign_in(authorized_user)
+          get "#{inquiry_path}/#{invalid_id}"
+        end
 
-        it_behaves_like 'common error handling', :bad_request, 'invalid_inquiry_error',
-                        'AskVAApi::V0::InquiriesController::InvalidInquiryError'
-      end
-    end
+        it { expect(response).to have_http_status(:unprocessable_entity) }
 
-    context 'when an error occur' do
-      before do
-        allow(Crm::Service).to receive(:new).and_raise(ErrorHandler::ServiceError)
-        sign_in(authorized_user)
-        get "#{inquiry_path}/#{id}"
+        it_behaves_like 'common error handling', :unprocessable_entity, 'service_error',
+                        'AskVAApi::Inquiries::InquiriesRetrieverError: ' \
+                        'Data Validation: No Inquiries found by ID A-20230305-30617'
       end
-
-      it { expect(JSON.parse(response.body)).to eq('error' => 'ErrorHandler::ServiceError') }
     end
 
     context 'when user is not signed in' do
       before do
-        get "#{inquiry_path}/#{id}"
+        get "#{inquiry_path}/#{valid_id}"
       end
 
       it { expect(response).to have_http_status(:unauthorized) }