title: Telegram bot not getting @mention updates from group
body: <p>I have a bot in a group and until some days ago I could send messages to it by <code>@mentioning</code> it by username. Now it doesn't seem to work anymore. I can send <code>/commands</code> and the bot receives them just fine and if I disable privacy my bot can receive all messages.</p>
  
  <p>Was there a change server side? How would I go about debugging this further?</p>
  
  <p>In summary</p>
  
  <pre><code>curl -XPOST https://api.telegram.org/bot[token]/getUpdates
  </code></pre>
  
  <p>returns an empty array of results after <code>@mentioning</code> my bot by username in a group but non-empty results when sending a <code>/command</code>.</p>