What does the VARTA error `provider_unavailable` mean?

HTTP status: 503  ·  Type: provider_error

What it means

Reserved as the fallback code for an unrecognised "provider unavailable" failure.

What causes it

Cause not yet documented as a live path under this exact code — it is the status fallback for a /v1 handler that raises an unmapped 503 (backend/app/api/v1/errors.py). The one known 503 case today, no telephony provider configured, uses the more specific telephony_not_configured instead.

What to do

Retry with backoff, or check whether telephony_not_configured is the more precise explanation.