curl --request POST \
  --url https://sandbox.api.fantasyfutbol.app/v1/user \
  --header 'Content-Type: application/json' \
  --header 'x-api-key: <api-key>' \
  --data '
{
  "users": [
    {
      "external_id": "<string>",
      "display_name": "<string>"
    }
  ]
}
'

{
  "statusCode": 123,
  "message": "<string>",
  "data": [
    {
      "id": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
      "user_id": 123,
      "external_id": "<string>",
      "is_active": true,
      "display_name": "<string>",
      "created_at": "2023-11-07T05:31:56Z",
      "updated_at": "2023-11-07T05:31:56Z"
    }
  ]
}