curl --request GET \
  --url https://api.prod.getdex.com/v1/groups/{groupId}/contacts \
  --header 'Authorization: Bearer <token>'

{
  "error": true,
  "data": {
    "items": [
      {}
    ],
    "nextCursor": "3c90c3cc-0d44-4b50-8888-8dd25736052a",
    "count": 123
  }
}