vocapablesubscription_plan_change_conflict
The frozen renewal proposal, owner confirmation, existing commitment, complete provider billing source or paid successor is not proven. Recover the original operation or dismiss an undispatched proposal; no unknown provider request is repeated.
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/subscription_plan_change_conflict",
"title": "…",
"status": 409,
"detail": "…",
"instance": "/v1/…"
}