diff --git a/app/api/services/repayment.py b/app/api/services/repayment.py
index 43da420..01ebe87 100644
--- a/app/api/services/repayment.py
+++ b/app/api/services/repayment.py
@@ -73,7 +73,7 @@ class RepaymentService(BaseService):
 
                 # Simulated processing logic
                 response_data = {
-                    "transaction_id": transaction_id,
+                    "transactionId": transaction_id,
                     "customerId": customer_id,
                     "productId": product_id,
                     "debtId": loan_id,