// Client error
409 Conflict
The request conflicts with the current state of the target resource. The caller may be able to resolve the conflict and resubmit.
Common causes
- An idempotency key is reused with a different payment body.
- The current payment state forbids the requested transition.
- Concurrent edits conflict with saved resource state.
Troubleshooting
- Read the error code and current state.
- Fetch fresh resource data before resolving an edit conflict.
- Do not blindly retry payment creation. For a failed If-Match precondition, 412 is the more specific status.
HTTP example
POST /payments HTTP/1.1
Host: api.example.com
Content-Type: application/json
Idempotency-Key: example-payment-001
{"amount":5000,"currency":"EUR"}
HTTP/1.1 409 Conflict
Content-Type: application/json
{"code":"idempotency_conflict","message":"Key already used with different input"}Related status codes
// GET STARTED
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Use REST Test to send a request and review its status, headers, timing and body together.