diff --git a/wallet/v1/msg.proto b/wallet/v1/msg.proto
index 445526e..7bcf100 100644
--- a/wallet/v1/msg.proto
+++ b/wallet/v1/msg.proto
@@ -492,7 +492,7 @@ message LockAssetReq {
 
 message AssetDiscountReq {
   string code = 1;
-  string asset_id = 2;
+  int64 asset_id = 2;
   optional double amount = 3; // calculate discount amount
 }