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

# Sandbox subject conflict

> The reserved sandbox subject id is already taken by a regular provisioned subject.

This page is the resolution target of the RFC 9457 `type` URI on every `sandbox_subject_conflict` problem body: `https://docs.get-exo.com/errors/sandbox_subject_conflict`.

**HTTP status: `409` Conflict**.

```json theme={"theme":{"light":"github-light-default","dark":"github-dark-default"}}
{
  "type": "https://docs.get-exo.com/errors/sandbox_subject_conflict",
  "title": "Sandbox subject conflict",
  "status": 409,
  "detail": "The reserved sandbox subject id is taken by a regular subject.",
  "code": "sandbox_subject_conflict",
  "requestId": "req_9f2c41ab7d0e5c18"
}
```

## Why it happens

The sandbox partition is addressed by a reserved subject id. If that id was provisioned as an ordinary subject, the sandbox cannot claim it without silently colliding with real data.

## How to fix it

* Erase or rename the colliding subject with `DELETE /v1/subjects/{subject_id}`, then retry.
* If the colliding subject holds real content, move it to a different id before erasing.

## Related

* [`conflict`](/errors/conflict)
* [`permission_denied`](/errors/permission_denied)
* [Errors](/platform/errors) for the envelope and the full catalogue