GUARDIAN_MISMATCH

The guardian in the transaction is not the sender’s active guardian.

HTTP status	422
Group	Relay path
Retryable	No — sending it again changes nothing
Re-sign	NONE — do not ask the user to sign anything

What happened

The account’s guardian on chain differs from the one named in the transaction.

What to do

Read the account’s active guardian from the network and rebuild.

The problem document

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

{
  "type": "https://docs.co-relayer.com/errors/guardian-mismatch",
  "title": "The guardian in the transaction is not the sender’s active guardian.",
  "status": 422,
  "detail": "A sentence about this specific occurrence.",
  "instance": "req_01JB…",
  "code": "GUARDIAN_MISMATCH",
  "retryable": false,
  "resign": "NONE",
  "hint": "Read the account’s active guardian from the network and rebuild."
}

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