FREE_FLOW_UNAVAILABLE

The free-transaction budget for this period is spent.

HTTP status	503
Group	Relay path
Retryable	Yes — the same request may be sent again
Re-sign	SAME_BYTES — resend the transaction you already have, byte for byte

What happened

Free relays come out of a separate house budget so they can never eat into paid capacity.

What to do

Pay the gas yourself for this one, or retry later. Paid relaying is unaffected.

The problem document

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

{
  "type": "https://docs.co-relayer.com/errors/free-flow-unavailable",
  "title": "The free-transaction budget for this period is spent.",
  "status": 503,
  "detail": "A sentence about this specific occurrence.",
  "instance": "req_01JB…",
  "code": "FREE_FLOW_UNAVAILABLE",
  "retryable": true,
  "resign": "SAME_BYTES",
  "hint": "Pay the gas yourself for this one, or retry later. Paid relaying is unaffected."
}

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