curl --request POST \
  --url https://api.weblinq.dev/v1/system/update-user-plan \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "userId": "<string>",
  "plan": "free"
}
'

{
  "success": true,
  "data": {
    "userId": "<string>",
    "plan": "free",
    "updatedBy": "<string>",
    "updatedAt": "<string>"
  },
  "requestId": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
  "timestamp": "2023-11-07T05:31:56Z",
  "creditsCost": 123
}