Problems·HTTP 422
invalid-challenge
The proof-of-work challenge was not accepted.
What it means
Every sign-in spends a solved ALTCHA challenge. This one was missing, malformed, unsolved, expired (they last five minutes) or already used.
What to do
Get a new challenge from POST /v1/sign-in-challenges and solve it. einvoicing login does this for you.
Example
Sent as application/problem+json (RFC 9457). Branch on type, which is stable. Never branch on title or detail, which are prose and may change.
{ "type": "https://www.einvoicing.dev/problems/invalid-challenge", "title": "The proof-of-work challenge was not accepted.", "status": 422, "detail": "…"}All problem types
Every error the API can return, with what to do about each.
API reference
Every operation, its parameters and the errors it can answer with.