curl --request POST \
  --url https://api.sonderplan.com/v2/custom-field \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "name": "Booking Type",
  "description": "Select the type of booking",
  "type": "select",
  "options": [
    {
      "id": "4934",
      "name": "Video Editing",
      "order": "2"
    }
  ],
  "module": "booking",
  "order": 3,
  "required": true,
  "update_key": "2_1_8942"
}'

{
  "success": {
    "id": 1
  }
}