title: Call and online meeting bot - Peer to peer call is terminated automatically
body: <p>I am trying to develop a simple bot that is supposed to answer incoming call made in personal chat with bot. The bot is employing application hosted media to play or get access to media streams. I am making use of classes and controllers that are implemented in <a href="https://github.com/microsoftgraph/microsoft-graph-comms-samples/tree/master/Samples/V1.0Samples/LocalMediaSamples/HueBot" rel="nofollow noreferrer">Huebot sample project at Github</a>. The bot is registered on MS Azure and i am using <code>ngrok</code> for local testing and debugging. While debugging after making the call, breakpoints are hit that are placed in '<code>CallsOnIncoming</code>' or '<code>CallsOnUpdated</code>' event handlers. So my bot configurations over Azure and in MS Teams seem to be correct. For setting up media platform, I have installed the wildcard SSL certificated issued by <code>Let's Encrypt</code> and CName records are created for corresponding tcp URLs exposed by ngrok. The environment is multi-tenant i.e. bot registration is done on another tenant, while bot is installed and tested in MS Teams on another tenant.
  These are Media platform settings:</p>
  <pre><code> MediaPlatformInstanceSettings = new MediaPlatformInstanceSettings()
                      {
                          CertificateThumbprint = &quot;0B687..................&quot;,
                          InstanceInternalPort = 8445,
                          InstancePublicPort = 15410,
                          InstancePublicIPAddress = new IPAddress(0x0),
                          ServiceFqdn = &quot;4.mycustomdomain.com&quot;,
  
                      },
  </code></pre>
  <p>Here's the snapshot for ngrok:
  <a href="https://i.stack.imgur.com/HGEjy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/HGEjy.png" alt="enter image description here" /></a></p>
  <p>The problem is, when call is made to the bot, after 5 to 10 seconds call is terminated automatically. Whereas he Call status should turn to 'Established' and the call shouldn't end until user does this.Please guide, what could be wrong.</p>