# E01005 — IdempotencyKeyReuse

This idempotency key was already used with a different request.

- **HTTP status**: `409`
- **Type**: `conflict_error`
- **Name**: `IdempotencyKeyReuse`

## What to do

The request conflicts with the current state of the resource, including idempotency conflicts (`E01004`, `E01005`). Fetch the resource's current state and reconcile before retrying. For idempotency conflicts, reuse the original request body with the original key, or mint a new key for a genuinely new request.

## Related

- [Idempotency](/docs/api/idempotency): safe retries and key reuse rules
- [E01xxx — Infrastructure](/docs/api/errors/E01xxx): every code in this range
- [Errors](/docs/api/errors): the full wire contract, status mapping, and error catalog
- [Error handling](/docs/guides/errors): branching on `type` and `code`, validation details, and `vendor_code`