diff --git a/app/models/transaction.py b/app/models/transaction.py
index 20030d9..5bde2db 100644
--- a/app/models/transaction.py
+++ b/app/models/transaction.py
@@ -27,7 +27,7 @@ class Transaction(db.Model):
         # if cls.query.filter_by(transaction_id=transaction_id).first():
         #     raise ValueError("Duplicate Transaction")
 
-        if cls.query.filter( and_( transaction_id=transaction_id,type=type) ).first():
+        if cls.query.filter( and_( cls.transaction_id ==transaction_id, cls.type==type) ).first():
             raise ValueError("Duplicate Transaction")