CalenderList.List（）。执行（）不返回，谷歌日历API

Question

我正在使用Google日历API，以检索指定日历的所有事件。在设置我的凭据并调用以下内容后，获取所有日历的列表：

     var test = service.Calendars.Get(id).Execute();

Execite（）正在调用谷歌服务器，但我没有得到该通话的响应。并且它处于这种空闲状态。

public static ServiceAccountCredential Authenticate（）         {

        string serviceAccountEmail = "...@developer.gserviceaccount.com";
        string keyFilePath = @"filepath";

        // what googleApi features to access
           _scopes = new string[]
        {
            CalendarService.Scope.Calendar, // Manage your calendars
            CalendarService.Scope.CalendarReadonly // View your Calendars
        };

        var certificate = new X509Certificate2(keyFilePath, "notasecret", X509KeyStorageFlags.Exportable);

        ServiceAccountCredential credential = new ServiceAccountCredential(
             new ServiceAccountCredential.Initializer(serviceAccountEmail)
             {

                 Scopes = _scopes
             }.FromCertificate(certificate));


        return credential;
    }



 public class GoogleCalenderRepository
 {
    ServiceAccountCredential _credentials;

    public GoogleCalenderRepository()
    {
        _credentials = GoogleServiceAccountAuthentication.Authenticate();
    }
    // use async and await
    public string RoomAvailability()
    {
        CalendarService service = new CalendarService(new BaseClientService.Initializer()
        {
            HttpClientInitializer = _credentials,
            ApplicationName = "My Project",
        });

        var calender = service.Calendars.Get("@...group.calendar.google.com").Execute();

        return null;
    }
 }

编辑：当我在输出屏幕中调用Execute（）时，我得到：

线程0x13f4已退出，代码为0（0x0）