CHALLENGE_INVALID

The signed challenge did not verify.

HTTP status	401
Group	Platform
Retryable	No — sending it again changes nothing

What happened

It was already used, has expired, or was signed by a different key.

What to do

Request a new challenge and sign that one.

The problem document

Every error is application/problem+json (RFC 9457) with the same shape:

{
  "type": "https://docs.co-relayer.com/errors/challenge-invalid",
  "title": "The signed challenge did not verify.",
  "status": 401,
  "detail": "A sentence about this specific occurrence.",
  "instance": "req_01JB…",
  "code": "CHALLENGE_INVALID",
  "retryable": false,
  "hint": "Request a new challenge and sign that one."
}

See the error model for what each member means and how to handle unknown codes.