INSUFFICIENT_SENDER_BALANCE

The sender cannot cover the value it is trying to move.

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

CoRelayer pays the gas, not the amount. A transfer whose value the sender does not hold would fail on chain and still cost the relayer the full fee.

What to do

Fund the sender, or lower value, then relay.

The problem document

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

{
  "type": "https://docs.co-relayer.com/errors/insufficient-sender-balance",
  "title": "The sender cannot cover the `value` it is trying to move.",
  "status": 422,
  "detail": "A sentence about this specific occurrence.",
  "instance": "req_01JB…",
  "code": "INSUFFICIENT_SENDER_BALANCE",
  "retryable": false,
  "resign": "NONE",
  "hint": "Fund the sender, or lower `value`, then relay."
}

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