void Pusher_OnNotificationFailed(object sender, NotificationFailedEventArgs <ApnsNotification, ApnsResult> args)
        {
            _logger.LogError(args.Exception, "Notification failed. Code: {0}, reason: {1}", args.ResultCode, args.Reason);

            switch (args.ResultCode)
            {
            case ApnsResult.BadRequest:
                if (args.Reason.Equals("BadDeviceToken"))
                {
                    OnInvalidToken?.Invoke(this, new InvalidTokenEventArgs(args.Token));
                }

                break;

            case ApnsResult.TokenExpired:
                OnInvalidToken?.Invoke(this, new InvalidTokenEventArgs(args.Token));
                break;
            }
        }
 static void OnNotificationFailed(object sender, NotificationFailedEventArgs <ApnsNotification, ApnsResult> args)
 {
     Console.WriteLine("Notification failed. Code: {0}, Reason: {1}", args.ResultCode, args.Reason);
 }