diff --git a/app/workflow/approve.py b/app/workflow/approve.py
index c2b3c39..44dbfc7 100644
--- a/app/workflow/approve.py
+++ b/app/workflow/approve.py
@@ -99,7 +99,7 @@ def create_approve_graph(
             json={
               "inputs": {
                 "approve_pos_level": user_cls.pos.pos_level,
-                "amount": state.get('input_amount')
+                "amount": str(state.get('input_amount'))
               },
               "user": "abc-123"
             },