curl --request GET \
  --url https://api.gcore.com/billing/v3/trials \
  --header 'Authorization: <api-key>'

{
  "count": 123,
  "next": "https://api.gcore.com/billing/v3/trials?offset=20&limit=10",
  "previous": "https://api.gcore.com/billing/v3/trials?offset=10&limit=10",
  "result": [
    {
      "id": 123,
      "client_id": 123,
      "client_company": "Client Company",
      "product_id": 123,
      "product_internal_name": "CDN",
      "product_name_en": "CDN",
      "plan_id": 123,
      "plan_name_en": "Plan name",
      "days_limit": 123,
      "started_at": "2023-11-07T05:31:56Z",
      "ended_at": "2023-11-07T05:31:56Z",
      "created_at": "2023-11-07T05:31:56Z",
      "options": [
        {
          "id": 123,
          "trial_id": 123,
          "feature_id": 123,
          "name_en": "Trial traffic volume",
          "description_en": "Traffic volume given to a client during the trial.",
          "internal_name": "CDN_TRIAL_TRAFFIC_LIMIT",
          "unit_id": 123,
          "value": 300,
          "is_limit": true,
          "used_value": "124,00000000",
          "feature_name_en": "CDN-HTTP/HTTPS Delivery (GB)",
          "unit_name_en": "GB",
          "updated_at": "2023-11-07T05:31:56Z"
        }
      ]
    }
  ]
}