⚠️ Callback Instructions · Must Read Before Integration!

1. Payment Amount Explanation

   After receiving a successful payment callback, please use the orderActualAmount field in the callback parameters as the actual payment amount paid by the consumer to process the transaction, to avoid merchant fund loss caused by inconsistent payment amounts.

2. Null Check for Callback/Query Interfaces

   Certain fields in the order may return null values in different business scenarios or statuses. For example, when waiting for payment, the order's payment time may be empty. Merchants must perform null checks on all fields during integration to avoid errors during query/callback.

​ 3.Duplicate Callback

​ The system may retry callbacks under certain conditions. Developers must ensure that the following content is correctly returned in the callback response to confirm that the system recognizes the response as successful and stops retrying:

{ ``  "code": 200, ``  "success": true ``}

1. IP Whitelist Settings (Client Callback Service Must Be Whitelisted)

​ Please add the public IP of the callback service to the whitelist input box in [Developer Center → API KEY] to ensure that the callback request can be accessed normally.

1. Common Issues with Callback Failures: IP Restrictions

   Please ensure that the following IPs are all added to the whitelist:

   • All public IPs of the server (ordering/callback)
   • Public IP of the merchant's callback address server
   • Available outbound IPs (if using cloud provider load balancing, etc.)

​ 3.AccessKey Effectiveness Explanation

​ After creating the AccessKey, it typically takes about 2 minutes to become active. Please ensure that initialization synchronization has been completed before use. If you encounter ACCESS_KEY_INVALID, please try again later.