CHAIN_ID_MISMATCH

The transaction was signed for a different network than this host serves.

HTTP status	400
Group	Relay path
Retryable	No — sending it again changes nothing
Re-sign	NONE — do not ask the user to sign anything

What happened

The chainID inside the signed transaction is not the chain id of this API host. Mainnet is 1, devnet staging is D.

What to do

Rebuild the transaction with the chain id from GET /v1/network on the host you are calling, and sign it again.

The problem document

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

{
  "type": "https://docs.co-relayer.com/errors/chain-id-mismatch",
  "title": "The transaction was signed for a different network than this host serves.",
  "status": 400,
  "detail": "A sentence about this specific occurrence.",
  "instance": "req_01JB…",
  "code": "CHAIN_ID_MISMATCH",
  "retryable": false,
  "resign": "NONE",
  "hint": "Rebuild the transaction with the chain id from `GET /v1/network` on the host you are calling, and sign it again."
}

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