funding_idempotency_conflict
The supplied manual-funding idempotency key already names a different amount or currency. Retry the original request, or choose a new key for a new Checkout Session.
Problem shape
Every non-2xx response is an RFC 9457 application/problem+json body. The type URI below is stable and machine-matchable, so branch on the final path segment (the code) and treat the status as redundant confirmation. See the error-handling guide.
{
"type": "https://docs.vocapable.com/errors/funding_idempotency_conflict",
"title": "…",
"status": 409,
"detail": "…",
"instance": "/v1/…"
}