title: Botframework v4 - Facebook Channel - Operation returned an invalid status code 'Forbidden`
body: <p>Last year I developed a chatbot with Microsoft Bot Framework that I integrated in the Facebook Messenger of a page. Everything worked fine until 16th of December (last successful log). The page is not used by a lot of people therefore the application might have worked also longer than that.</p>
  <p>Today I tried to use the chatbot again and I did not get any response. In the Logs I just found the error message &quot;Operation returned an invalid status code 'Forbidden`&quot;.</p>
  <p>After a bit of Debugging I found out that the problem is sending messages back to the Facebook Messenger.</p>
  <pre><code>context.SendActivityAsync(...)
  </code></pre>
  <p>I did not change any configuration within my Azure Bot Channel registration recently. I am aware of the privacy changes within the Facebook API, but as I already struggle with sending a simple text response like &quot;Hi&quot; I assume that cannot be the problem. Also the permission scheme has changed for Facebook apps. I have the permission for &quot;pages_messaging&quot;. Do I need another permission now? Or did I miss another change in the Facebook API?</p>
  <p>Technical Details:</p>
  <ul>
  <li>Facebook API Version v6 (tried also v9 but no change in behavior)</li>
  <li>Chatbot based on .Net Core 2.1</li>
  <li>Bot Builder SDK v 4.11</li>
  </ul>
  <p>Any hints what I did wrong or where I can look for further information is much appreciated.</p>
  <p><strong>Edit</strong>: I tried to add a new page to my Facebook App and get following message:
  <a href="https://i.stack.imgur.com/9Dewg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/9Dewg.png" alt="enter image description here" /></a></p>
  <p>There is a hint that a permission is missing, but I cannot find out which one I require. As I only send responses to FAQ's and if required handover to the customer service inbox I just requested the &quot;pages_messaging&quot; permission. Do I require any other permission now?</p>