title: Azure IoT Hub: What happens when sending data if daily message limit is exceeded?
body: <p>We are using Azure's IoT Hub as backend for our IoT solution. We noticed that we had an unexpected spike in message amount during one day, and we exceeded our daily limit of 400k messages.</p>
  
  <p>From client application's logs we couldn't find anything out of the normal: based on the logs it seems that client kept sending data despite the daily limit being exceeded.</p>
  
  <p>So my question is: what happens when client application sends data using <code>DeviceClient.SendEventBatchAsync</code> when daily message limit is already exceeded? Are the messages just dropped cold blooded despite there was no exceptions? Or is there happening something that I have failed to catch? We are using C# .NET <code>Microsoft.Azure.Devices.Client</code> version 1.19.0 and sending the data using MQTT protocol.</p>