private async void Callback(object state) { if (!_mqttService.IsConnected()) { return; } await _mqttService.Send(_deviceState.DeviceId, "2000", _deviceState.OperationTimeInSec.ToString()); if (tickCounter % 10 == 0) { await _mqttService.Send(_deviceState.DeviceId, "2010", _deviceState.WorkingHour.ToString()); } }