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

# API key not found

> 404 — The referenced API key prefix does not exist.

The referenced API key prefix does not exist.

```json 404 application/problem+json theme={null}
{
  "type": "https://docs.permitcore.io/errors/api-key-not-found",
  "title": "API key not found",
  "status": 404,
  "detail": "…",
  "instance": "/v1/keys/pk_abc123/usage",
  "request_id": "req_1f07fb45782b445e9f6312ba23921234"
}
```

Every PermitCore error is [RFC 9457](https://www.rfc-editor.org/rfc/rfc9457)
`application/problem+json`. **Branch on `type` (a stable URI)**, not on `title`
or `detail` (human-readable, may change).

## When it occurs

A key-management or usage request referenced a `key_prefix` that does not belong to your account (or was already deleted).

## How to fix

List your keys via `GET /v1/keys` to confirm the prefix. See [API key management](/api-reference/keys).

**Not retryable** — fix the request before resubmitting; retrying unchanged returns the same error.

See the full [error catalog](/errors) for the response shape and retry matrix.
Every response carries an `x-request-id` header — include it in any support request.