private async void sendTimer_Tick(object sender, EventArgs e)
 {
     if (!isConnected)
     {
         return;
     }
     if (!canCommunicate)
     {
         return;
     }
     var textMessage = new Messenger.TextMessage
     {
         UserId       = userId,
         TextMessage_ = (++sendCount).ToString(),
         TimeStamp    = GetServerTimeStamp()
     };
     var result = await client.SendTextMessageAsync(textMessage);
 }