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

# not_found (404)

> The crew member or vessel isn't attributed to you.

Returned when the requested crew member or vessel isn't on one of your attached
vessels — or doesn't exist. The two are **deliberately indistinguishable** so
you cannot enumerate the CrewPass user base.

```json theme={null}
{ "error": { "code": "not_found", "message": "no crew member with that id on your attached vessels" } }
```

**Fix**

* Confirm the vessel is attached to you (`vessels/lookup` returns `attached`).
* Confirm the crew member appears in your `GET /fleet` results.
* A crew member who genuinely exists but sits outside your fleet will always
  return `404`, never `403`.