diff --git a/apps/indexer/Cargo.lock b/apps/indexer/Cargo.lock
index 38bbdec2..8c7a4134 100644
--- a/apps/indexer/Cargo.lock
+++ b/apps/indexer/Cargo.lock
@@ -3109,6 +3109,7 @@ dependencies = [
  "env_logger",
  "futures",
  "log",
+ "mongodb",
  "serde",
  "serde_json",
  "starklane_indexer",
diff --git a/apps/indexer/refund/Cargo.toml b/apps/indexer/refund/Cargo.toml
index 9fde5038..555a02c9 100644
--- a/apps/indexer/refund/Cargo.toml
+++ b/apps/indexer/refund/Cargo.toml
@@ -9,11 +9,12 @@ anyhow = "1.0"
 clap = { version = "4.3.19", features = ["derive", "env", "string"] }
 csv = "1.3.0"
 env_logger = "0.10.0"
-log = "0.4.17"
 futures = "0.3.28"
+log = "0.4.17"
+mongodb = "2.6.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
+starknet = "0.10.0"
 tokio = { version = "1", features = ["full"] }
 
 starklane_indexer = { version = "0.1.0", path= ".."}
-starknet = "0.10.0"
diff --git a/apps/indexer/refund/src/bin/send_refund.rs b/apps/indexer/refund/src/bin/send_refund.rs
index 3c4d65b1..56010aa6 100644
--- a/apps/indexer/refund/src/bin/send_refund.rs
+++ b/apps/indexer/refund/src/bin/send_refund.rs
@@ -3,7 +3,10 @@ use std::time::Duration;
 use anyhow::{anyhow, Result};
 use clap::Parser;
 
+use mongodb::{bson::doc, options::ClientOptions, Client, Collection};
 use refund::Refund;
+use serde::{Deserialize, Serialize};
+use starklane_indexer::{storage::extract_database_name, utils::normalize_hex};
 use starknet::{
     accounts::{Account, Call, ConnectedAccount, ExecutionEncoding, SingleOwnerAccount},
     core::{
@@ -14,6 +17,49 @@ use starknet::{
     signers::{LocalWallet, SigningKey},
 };
 
+#[derive(Debug, Serialize, Deserialize)]
+struct RefundSend {
+    pub l1_hash: String,
+    pub l2_hash: String,
+    pub refund: Refund,
+}
+
+struct MongoStore {
+    refunded: Collection<RefundSend>,
+}
+
+impl MongoStore {
+    pub async fn new(connection_string: &str, db_name: &str) -> Result<MongoStore> {
+        let client_options = ClientOptions::parse(connection_string).await?;
+        let client = Client::with_options(client_options)?;
+        let db = client.database(db_name);
+        let refunded = db.collection::<RefundSend>("refunded");
+
+        Ok(MongoStore { refunded })
+    }
+
+    pub async fn add(&self, l2_hash: String, refund: &Refund) -> Result<()> {
+        let doc = RefundSend {
+            l1_hash: refund.tx_hash.clone(),
+            l2_hash: normalize_hex(&l2_hash).unwrap(),
+            refund: refund.clone(),
+        };
+        self.refunded.insert_one(doc, None).await?;
+        Ok(())
+    }
+
+    pub async fn check(&self, l1_hash: String) -> Result<Option<RefundSend>> {
+        match self
+            .refunded
+            .find_one(doc! { "l1_hash": l1_hash}, None)
+            .await
+        {
+            Ok(r) => Ok(r),
+            Err(e) => Err(anyhow!("Failed to query DB: {:?}", e)),
+        }
+    }
+}
+
 #[derive(Parser, Debug)]
 #[clap(about = "Send refund")]
 struct Args {
@@ -49,9 +95,6 @@ fn refund_to_call(refund: &Refund) -> Call {
     let decimals = 8;
     let amount = refund.amount * (10_u64.pow(decimals) as f64);
     let amount = (amount as u128) * (10_u64.pow(token_decimals - decimals) as u128);
-    // FIXME: for testing purpose!!
-    let amount = amount / 100;
-    // FIXME
     let amount = FieldElement::from(amount);
     Call {
         to: token_address,
@@ -94,7 +137,6 @@ where
     }
 }
 
-
 #[tokio::main]
 async fn main() -> Result<()> {
     env_logger::init();
@@ -105,6 +147,9 @@ async fn main() -> Result<()> {
     let address = args.address;
     let private_key = args.private_key;
 
+    let dbname = extract_database_name(&args.mongodb)
+        .expect("Database name couldn't be extracted from the connection string");
+
     let provider = JsonRpcClient::new(HttpTransport::new(Url::parse(&rpc).unwrap()));
     let signer = LocalWallet::from(SigningKey::from_secret_scalar(
         FieldElement::from_hex_be(&private_key).unwrap(),
@@ -114,28 +159,49 @@ async fn main() -> Result<()> {
 
     let account =
         SingleOwnerAccount::new(provider, signer, address, chain_id, ExecutionEncoding::New);
+
     log::debug!("Account address: {:?}", account.address());
     let mut calls: Vec<Call> = vec![];
+    let mut refunds: Vec<Refund> = vec![];
+
+    let mongo = MongoStore::new(&args.mongodb, dbname).await?;
 
     let mut rdr = csv::Reader::from_path(input)?;
     for elem in rdr.deserialize() {
         let refund: Refund = elem?;
-        log::debug!("{:?}", refund);
+        if let Ok(Some(_check)) = mongo.check(refund.clone().tx_hash).await {
+            log::debug!("Already send: {:?}", refund);
+            continue;
+        }
+        log::debug!("To send: {:?}", refund);
         let call = refund_to_call(&refund);
         calls.push(call);
+        refunds.push(refund);
+    }
+
+    if calls.is_empty() {
+        log::info!("No refund to send");
+        return Ok(());
     }
-    // log::debug!("Calls: {:?}", calls);
 
-    let invoke = account
-        .execute(calls)
-        .send()
-        .await
-        .unwrap();
+    let invoke = account.execute(calls).send().await.unwrap();
     let provider = account.provider();
     log::debug!("Wait for transaction: {:?}", invoke.transaction_hash);
-    let result = watch_tx(provider, invoke.transaction_hash, Duration::from_millis(10000)).await;
+    let result = watch_tx(
+        provider,
+        invoke.transaction_hash,
+        Duration::from_millis(10000),
+    )
+    .await;
     match result {
-        Ok(_) => Ok(()),
-        Err(e) => Err(anyhow!("Transaction failed! {:?}", e))
+        Ok(_) => {
+            for refund in refunds {
+                let l2_hash = format!("{:#064x}", invoke.transaction_hash);
+                let l2_hash = normalize_hex(&l2_hash).unwrap();
+                mongo.add(l2_hash, &refund).await?
+            }
+            Ok(())
+        }
+        Err(e) => Err(anyhow!("Transaction failed! {:?}", e)),
     }
 }