title: Azure Service Bus subscription not received all messages in topic
body: <p>I am following this <a href="https://docs.microsoft.com/en-us/azure/service-bus-messaging/service-bus-dotnet-how-to-use-topics-subscriptions" rel="nofollow noreferrer">https://docs.microsoft.com/en-us/azure/service-bus-messaging/service-bus-dotnet-how-to-use-topics-subscriptions</a> to learn how to use Service Bus Topic and Subscriptions to receive messages.</p>
  
  <p>It 1st sends 10 messages and then receives the 10 messages.</p>
  
  <p>However, once I finished coding and ran the code, the 10 messages were sent, but I only received 8 of them, there were 2 of messages still in the subscription.</p>
  
  <p>Could anyone enlighten me on</p>
  
  <ol>
  <li>why this happened? </li>
  <li>Is it okay to happen? </li>
  <li>how to prevent it from happening again? </li>
  <li>once happened, what is the best practice to handle this situation?</li>
  </ol>