curl --request DELETE \
  --url https://api.example.com/v1/prior-auth/authorizations/{authorization_id}/attachments/{attachment_id}

{
  "error": {
    "code": "auth_provider_unavailable",
    "message": "<string>",
    "retryable": false,
    "details": {},
    "issues": [
      {
        "errorType": "<string>",
        "location": [
          "<string>"
        ],
        "message": "<string>"
      }
    ]
  },
  "requestId": "<string>"
}