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

# 409 - Rejected

An Already Exists error is returned on operations which violate an at-most-once or uniqueness constraint.

For example, an Already Exists error will be returned if:

* Create Order is called with an already-used `ref_id`
* Create Profile is called with an already-existing profile nickname
* Accept Quote is called on a quote which has already been accepted

An Already Exists error has the following "meta" fields:

* `existing`: The existing record which is the subject of the conflict (for example, the existing order with the same `ref_id`)

An Already Exists error may be benign if the client is retrying an earlier attempted operation which the client believes may have failed.

However, if the request is not a retry, then resolving the error requires changing the request to avoid the conflict.

<CodeGroup>
  ```json Example theme={null}
  {
    "detail": "nickname already exists",
    "meta": {
      "existing": {
        "id": "b7b77d82-e6a7-4ae9-9904-36231aedf985",
        "nickname": "existing nickname"
      }
    },
    "status": 409,
    "title": "Already Exists",
    "type": "https://developer.paxos.com/docs/v2/problems/already-exists"
  }
  ```
</CodeGroup>