How to use api for gpt

I want to use my api for building my GPT,but when I add it to the action, it showed as follows:

{
  "response_data": {
    "error": "no authentication methods were specified",
    "error_code": "InvalidParameter",
    "link": "https://realm.mongodb.com/groups/65aa8beea41b471baec12200/apps/65aa99a65653e22847f69462/logs?co_id=65ad0cd4ec75483f9a0be040"
  },
  "status_code": 400,
  "action_id": "g-b3b70cc174a9388c49e69ad8708ed4e6e219d6c9"
}

I had used the api key for authentication. Why?