curl --request GET \
  --url https://api.pamhq.com/v1/campaigns/{id}/results \
  --header 'Authorization: Bearer <token>'

{
  "data": {
    "campaign_id": "<string>",
    "metrics": {
      "total": 123,
      "initiated": 123,
      "engaged": 123,
      "scheduled": 123,
      "opted_out": 123,
      "completed": 123,
      "error": 123
    }
  },
  "meta": {
    "request_id": "<string>"
  }
}