title: Bot framework: “Sorry, my bot code is having an issue”. Fixed bug but how to restart conversation?
body: <p>I have a simple Bot created using Microsoft Bot Framework running on Azure and it was working fine on all channels. Until yesterday when it stopped working on Facebook messenger when a user chose a particular untested option.</p>
  
  <p>These are the lines that get executed when the rogue option is selected:</p>
  
  <pre><code>string replyText = "I am not yet ready to answer this question. Please choose another option.";
  
              switch (appointmentBookType){
                  case Option1:
                      //Call Option1 Dialog.
                      break;
                  case Option2:
                      //Call Option2 Dialog.
                      break;
  </code></pre>
  
  <p>I keep getting "Sorry, my bot code is having an issue" as a response to anything I type.</p>
  
  <p>This is the error I see in the Bot Framework developer portal for facebook messenger:
  "There was an error sending this message to your bot: HTTP status code InternalServerError"</p>
  
  <p>I am only using dialogs with some HeroCards.
  I do not use LUIS.</p>
  
  <p>I have fixed the bug by handling this previously unhandled conditions.
  Is there a way to restart the conversation after fixing the bug?</p>