curl --request GET \
  --url https://api.hubapi.com/account-info/v3/api-usage/daily/private-apps \
  --header 'Authorization: Bearer <token>'

{
  "results": [
    {
      "collectedAt": "2020-04-10T06:46:40.789Z",
      "currentUsage": 1,
      "fetchStatus": "SUCCESS",
      "name": "private-apps-api-calls-daily",
      "resetsAt": "2020-04-10T04:00:00Z",
      "usageLimit": 500000
    }
  ]
}