curl --request GET \
  --url https://app.freyavoice.ai/api/v2/campaign/{campaignId}/customers \
  --header 'Authorization: Bearer <token>'

{
  "success": true,
  "data": {
    "message": "<string>",
    "result": {
      "customers": [
        {
          "id": "<string>",
          "phoneNumber": "<string>",
          "properties": {},
          "retryStatus": {
            "attempts": 123,
            "lastAttemptAt": "2023-11-07T05:31:56Z",
            "nextRetryAt": "2023-11-07T05:31:56Z",
            "callIds": [
              "<string>"
            ]
          },
          "callCount": 123,
          "successfulCallId": "<string>",
          "createdAt": "<string>"
        }
      ],
      "propertyKeys": [
        "<string>"
      ],
      "pagination": {
        "total": 123,
        "limit": 123,
        "offset": 123
      },
      "statusCounts": {}
    }
  }
}