curl --request GET \
  --url https://api.hubapi.com/conversations/v3/custom-channels/{channelId}/channel-accounts \
  --header 'Authorization: Bearer <token>'

{
  "results": [
    {
      "active": true,
      "archived": true,
      "authorized": true,
      "channelId": "<string>",
      "createdAt": "2023-11-07T05:31:56Z",
      "id": "<string>",
      "inboxId": "<string>",
      "name": "<string>",
      "archivedAt": "2023-11-07T05:31:56Z"
    }
  ],
  "total": 123,
  "paging": {}
}