admin_second_factor_unavailable
This code is raised on a non-customer surface (the /internal voice-runtime audience or telephony provider callbacks). It is excluded from the customer OpenAPI document and is registered here so an operator reading a log line has one place to look.
This deployment cannot run the factor that was asked for: no email provider for the standard code, no account-security pepper, or (for authenticator enrolment only) no encryption keyring. 503 and never a silent downgrade - a deployment that cannot send a code has a closed console, not an open one. An unusable keyring affects enrolment alone; the emailed code needs no key.
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/admin_second_factor_unavailable",
"title": "…",
"status": 503,
"detail": "…",
"instance": "/v1/…"
}