diff --git a/apps/examples/uma-vasp-cli/package.json b/apps/examples/uma-vasp-cli/package.json
index 79d2737d..5a3f5cd3 100644
--- a/apps/examples/uma-vasp-cli/package.json
+++ b/apps/examples/uma-vasp-cli/package.json
@@ -45,7 +45,7 @@
     "@inquirer/prompts": "^1.1.3",
     "@lightsparkdev/core": "1.2.6",
     "@lightsparkdev/lightspark-sdk": "1.8.8",
-    "@uma-sdk/core": "^1.2.0",
+    "@uma-sdk/core": "^1.2.3",
     "chalk": "^5.3.0",
     "commander": "^11.0.0"
   },
diff --git a/apps/examples/uma-vasp/package.json b/apps/examples/uma-vasp/package.json
index 431b768c..3320106c 100644
--- a/apps/examples/uma-vasp/package.json
+++ b/apps/examples/uma-vasp/package.json
@@ -15,7 +15,7 @@
   "dependencies": {
     "@lightsparkdev/core": "1.2.6",
     "@lightsparkdev/lightspark-sdk": "1.8.8",
-    "@uma-sdk/core": "^1.2.0",
+    "@uma-sdk/core": "^1.2.3",
     "express": "^4.18.2",
     "uuid": "^9.0.0",
     "zod": "^3.22.4"
diff --git a/apps/examples/uma-vasp/src/SendingVasp.ts b/apps/examples/uma-vasp/src/SendingVasp.ts
index 9644614b..173f9432 100644
--- a/apps/examples/uma-vasp/src/SendingVasp.ts
+++ b/apps/examples/uma-vasp/src/SendingVasp.ts
@@ -961,7 +961,7 @@ export default class SendingVasp {
       requestUrl: requestUrl,
       senderProfile: payerPofile,
       pubKeys: pubKeys,
-      umaVersion: invoice.umaVersion,
+      umaVersion: invoice.umaVersions,
       invoiceUUID: invoice.invoiceUUID
     });
   }
@@ -998,7 +998,7 @@ export default class SendingVasp {
       // invoice data / utxo callback / etc not required
       undefined, undefined, undefined
     )
-    // In a real VASP, here you might push a notification to inform the sender that
+    // In a real VASP, here you might push a notification to inform the sender that
     // a new invoice has arrived.
     return {
       httpStatus: 200
diff --git a/packages/ui/package.json b/packages/ui/package.json
index f082c158..5b325de8 100644
--- a/packages/ui/package.json
+++ b/packages/ui/package.json
@@ -63,6 +63,7 @@
     "@simbathesailor/use-what-changed": "^2.0.0",
     "@svgr/core": "^8.1.0",
     "@tanstack/react-table": "^8.20.5",
+    "@uma-sdk/core": "^1.2.3",
     "@wojtekmaj/react-daterange-picker": "^5.5.0",
     "@wojtekmaj/react-datetimerange-picker": "^5.5.0",
     "@zxing/browser": "^0.1.1",
diff --git a/packages/ui/src/hooks/useFields.tsx b/packages/ui/src/hooks/useFields.tsx
index 23ded253..5d165f13 100644
--- a/packages/ui/src/hooks/useFields.tsx
+++ b/packages/ui/src/hooks/useFields.tsx
@@ -1,3 +1,4 @@
+import { isValidUmaAddress } from "@uma-sdk/core";
 import { diff } from "deep-object-diff";
 import { isObject } from "lodash-es";
 import { useCallback, useEffect, useMemo, useRef, useState } from "react";
@@ -21,6 +22,7 @@ const defaultMsgs = {
   code: "Code must be eight characters long.",
   password: "Password must be at least eight characters.",
   required: "This field is required.",
+  umaAddress: "Please enter a valid UMA address.",
 };
 
 const regexp = {
@@ -56,6 +58,10 @@ export const v: Validators = {
     (msg = defaultMsgs.code) =>
     (value) =>
       value.trim().length !== 8 ? msg : false,
+  umaAddress:
+    (msg = defaultMsgs.umaAddress) =>
+    (value) =>
+      !isValidUmaAddress(value) ? msg : false,
   required:
     (msg = defaultMsgs.required) =>
     (value) =>