Error Codes

Error code (code) indicates the processing result of API requests.

Success Response

Response Code	Description
`0`	Interface response successful

Important Note

code being 0 only means interface call succeeded, not transaction success. Transaction final status needs to be determined by transactionStatus.

Security Restriction Errors (S prefix)

Error Code	Description	Solution
`S01`	Invalid IP address	Check if merchant has configured IP whitelist and add calling server IP to whitelist
`S02`	Request timestamp deviation from server time too large	Sync client system time, ensure time difference within allowed range (±10 minutes)
`S03`	Signature verification failed	Check signature algorithm, key, and parameter order, confirm parameters involved in signature have not been modified
`S04`	Interface call frequency exceeded	Reduce call frequency, follow platform frequency limit rules
`S05`	Data decryption failed	Check code encryption logic or check if key settings are correct
`S06`	Insufficient permissions	Contact administrator to apply for permissions or check if permissions are correct
`S07`	TMK key does not exist or key expired	Re-obtain TMK
`S08`	Working key does not exist or key expired	Re-obtain working key
`S09`	Login session expired or not logged in	Log in again
`S10`	Request authentication failed	Check key settings or authentication algorithm calculation is correct
`S11`	Duplicate request	Use different X-Request-Id to initiate request again, or wait 10 minutes before retrying

Client Errors (C prefix)

Error Code	Description	Solution
`C01`	Request parameter missing	Ensure all required parameters are provided
`C02`	Request JSON format error	Check JSON structure, bracket matching, and data type validity
`C03`	Merchant does not exist or is disabled	Check if merchant ID is correct and confirm merchant status
`C06`	Duplicate request serial number	Ensure uniqueness of merchant request number, avoid duplicate submission
`C08`	Transaction locked (prevent concurrent operations)	Wait for current operation to complete before initiating new request, recommend business layer locking control
`C10`	Order already paid	Confirm order status through order query interface, no need to repeat operation
`C12`	Order does not exist	Check if order number is correct and order’s merchant
`C14`	Transaction amount exceeds allowed range	Check platform’s amount limit rules for this merchant/payment method, adjust request amount
`C15`	Refund amount exceeds original order amount or refundable balance	Verify original order amount and refunded amount, ensure total refund amount does not exceed refundable limit
`C24`	Original transaction status not allowed	Check transaction status

Merchant Configuration Errors (M prefix)

Error Code	Description	Solution
`M01`	Interface call permission insufficient or not activated	Apply for corresponding interface permission or renew
`M02`	Application does not exist or unavailable	Check if appId is correct and confirm application status on open platform
`M04`	Merchant has not activated this payment product or payment parameters not configured or configured incorrectly	Confirm merchant has activated corresponding payment product, complete payment parameter configuration

Payment Channel Errors (P prefix)

Error Code	Description	Solution
`P01`	Bank channel exception	Call order query interface to confirm transaction status, if unpaid order can retry

System Errors (E prefix)

Error Code	Description	Solution
`E01`	System busy, please try again later	Call order query interface to confirm transaction status, if unpaid order can retry
`E02`	Network timeout or error	Call order query interface to confirm transaction status, if unpaid order can retry
`E03`	Unknown exception	Call order query interface to confirm transaction status, if unpaid order can retry

Error Handling Recommendations

When encountering P01, E01, E02, E03 errors, should first call order query interface to confirm transaction status
If order is unpaid, can retry; if multiple attempts still fail, contact technical support
When encountering C08, C26, C27 and other concurrency-related errors, recommend retrying later