When something breaks

Find the symptom you are seeing. Every page here walks the checks in the order this catalogue recommends checking, not a record of how often each has turned out to be the actual cause, so you do not need to know an error code to start.

• The callback never arrives: a call returned 202, and nothing followed on your registered URL.
• Everything returns 401: every call fails the same way, not just one endpoint.
• The OTP never arrives: you requested an OTP and nothing reached the phone.
• Accepted, then nothing: discovery or linking started and stalled somewhere in the middle.
• Consent stuck in Requested: a consent request never moved to Granted or Denied.

If your symptom is not here, or you already have an error code in hand, the error codes reference is organised the other way, by code.