diff --git a/Polkadot/Polkadot-starter/package.json b/Polkadot/Polkadot-starter/package.json
index e17efbe..c4ce511 100644
--- a/Polkadot/Polkadot-starter/package.json
+++ b/Polkadot/Polkadot-starter/package.json
@@ -25,7 +25,8 @@
     "@subql/cli": "latest",
     "@subql/testing": "latest",
     "@subql/types": "latest",
-    "typescript": "^5.2.2"
+    "typescript": "^5.2.2",
+    "@subql/common-substrate": "^4.0.1"
   },
   "resolutions": {
     "ipfs-unixfs": "6.0.6"
diff --git a/Polkadot/Polkadot-starter/src/mappings/mappingHandlers.ts b/Polkadot/Polkadot-starter/src/mappings/mappingHandlers.ts
index ceb3c53..fff1c12 100644
--- a/Polkadot/Polkadot-starter/src/mappings/mappingHandlers.ts
+++ b/Polkadot/Polkadot-starter/src/mappings/mappingHandlers.ts
@@ -26,7 +26,7 @@ export async function handleEvent(event: SubstrateEvent): Promise<void> {
   // logger.info(JSON.stringify(event));
   const {
     event: {
-      data: [to, amount],
+      data: [, to, amount],
     },
   } = event;