title: Getting "(#100) Pages Public Content Access requires either app secret proof or an app token" issue when calling Facebook API?
body: <p>I am developing an app that syncs with users Facebook account and fetches Facebook page information. Initially, app asks for Login with Facebook and gets page list. After getting pages I am calling API to get posts associated with each page. Once I get post details then I am calling insight APIs to get insights of each post.
  This flow working fine with development mode but when I switch to Live mode I am getting the following error</p>
  <pre><code>      Client error: `GET https://graph.facebook.com/v4.0/100575944711552/feed` resulted in a `400 Bad Request` response:{&quot;error&quot;:{&quot;message&quot;:&quot;(#100) Pages Public Content Access requires either app secret proof or an app token&quot;,&quot;type&quot;:&quot;OAuthE (truncated...)
   {&quot;userId&quot;:1,&quot;email&quot;:&quot;superuser@corals.io&quot;,&quot;exception&quot;:&quot;[object] (GuzzleHttp\\Exception\\ClientException(code: 400): Client error: `GET https://graph.facebook.com/v4.0/100575944711552/feed` resulted in a `400 Bad Request` response:
  {\&quot;error\&quot;:{\&quot;message\&quot;:\&quot;(#100) Pages Public Content Access requires either app secret proof or an app token\&quot;,\&quot;type\&quot;:\&quot;OAuthE (truncated...)
  </code></pre>
  <p>From the details what I observed I am getting this error while using,</p>
  <pre><code>GET /v5.0/{page-id}/feed HTTP/1.1
  Host: graph.facebook.com
  </code></pre>
  <p>this endpoint. I am currently having 2 permissions approved,</p>
  <ol>
  <li>manage_pages     2. read_insights
  and app review team rejected 2 permissions saying the request is invalid and for this use case we don't require this which are,
  1.Page Mentions 2. user_posts</li>
  </ol>
  <p>Can anyone help me to understand what is the exact issue?</p>