> ## Documentation Index
> Fetch the complete documentation index at: https://docs.blujay.io/llms.txt
> Use this file to discover all available pages before exploring further.

# IDEMPOTENCY_REQUEST_MISMATCH

> Idempotency key reused with a different request

| HTTP status | Retryable |
| - | - |
| `409` | No |

## What happened

You sent an `Idempotency-Key` that was already used for a request with a different body or target.

## How to fix it

Use a new key for a new request. Reuse a key only to retry the exact same request.

## Example response

An illustrative example. The `message` wording and the contents of `details` vary; branch on `error.code`.

```json theme={null}
{
  "status": "error",
  "error": {
    "code": "IDEMPOTENCY_REQUEST_MISMATCH",
    "message": "Idempotency key reused with a different request",
    "type": "idempotency",
    "http_status": 409,
    "retryable": false,
    "doc_url": "https://docs.blujay.io/errors/idempotency-request-mismatch",
    "details": []
  },
  "trace_id": "trc_8f2a1c0e4b7d",
  "timestamp": "2026-10-14T17:30:48.000Z"
}
```

## Still stuck?

Email [support@blujay.io](mailto:support@blujay.io) with the `trace_id` from the error response. See [Errors](/errors.md) for the response format.


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