Errors, Retries & Idempotency

Read the business result, not only HTTP status

Open Platform can return HTTP 200 after a request is forwarded while the supplier business result is unsuccessful. Treat code=SUCCESS as the success condition and retain request_id, trace_id, and downstream_request_id for support.

Authentication and access failures

Code	Action
`APP_KEY_INVALID` / `001–008`	Confirm environment, application key, permission and outbound-IP whitelist.
`SIGN_ERROR` / `HUB_SIGNATURE_INVALID`	Rebuild the canonical string from the raw path, sorted query, body hash, timestamp, nonce and App Key.
`TIMESTAMP_EXPIRED` / `TIMESTAMP_EXPIRATION`	Synchronize server time and create a new request.
`NONCE_REPLAY`	Generate a new nonce; never repeat an old request verbatim.
`ACCESS_OVERCLOCKED`	Reduce concurrency and retry later with backoff.

Booking and order outcomes

Code family	Meaning and handling
`CENTER_FULL_ROOM`, `DISSATISFY_QUOTA`	No inventory; show the customer that the rate is unavailable and refresh products.
`PRICE_NEED_QUERY`, `HUB_CHARGE_PRICE`	Price changed or must be refreshed; rerun real-time product query and trial booking.
`DISSATISFY_*CLAUSE`	Guest, occupancy, room, booking or cancellation conditions are not met; correct the request rather than blindly retrying.
`HUB_ORDER_HAVE_EXISTED`, `CENTER_EXIST_ORDER`	Possible duplicate order; reconcile using your `coOrderCode` and query order details.
`CENTER_INSUFFICIENT_AMOUNT`	Insufficient credit balance; do not retry payment until balance is resolved.
`ORDER_CONFIRMING_CANNOT_CANCEL`	Order is being confirmed; wait for webhook/order result rather than issuing repeated cancels.

Retry decision

May retry safely: network failures, CONNECT_TIME_OUT, HUB_INTERNAL_TIMEOUT, and temporary downstream timeouts — only with a stable idempotency key for writes.
Do not blind-retry: validation, authentication, inventory, price, policy and duplicate-order errors. Correct or reconcile first.
For create, pay, cancel and checkout: persist your own request ID and idempotency key before sending, then reconcile before any retry.

For the full official code list, including invoice and checkout validation codes, see the G-Link Error Code reference.