title: Facebook Graph Api error "An unexpected error has occurred. Please retry your request later"
body: <p>I'm trying to retrieve all members in a Facebook group getting this error:</p>
  
  <pre><code> array(5) {
      ["message"]=&gt;
      string(66) "An unexpected error has occurred. Please retry your request later."
      ["type"]=&gt;
      string(14) "OAuthException"
      ["is_transient"]=&gt;
      bool(true)
      ["code"]=&gt;
      int(2)
      ["fbtrace_id"]=&gt;
      string(11) "AnfsXcdgM"
    }
  </code></pre>
  
  <p>Here is my code:</p>
  
  <pre><code>$this-&gt;_facebook = new Facebook\Facebook(array('app_id' =&gt; "$app_id",'app_secret' =&gt; "$secret",'default_graph_version' =&gt; 'v2.10'));
  
  $this-&gt;_facebook-&gt;setDefaultAccessToken($_SESSION['facebook_access_token']);
  
  $query = "/".$groupID."/members?fields=id,name,link,picture,first_name,last_name";
  
  try{
      $response = $this-&gt;_facebook-&gt;get($query);
      while($pagesEdge)
      {
       $pageDecoded = json_decode($pagesEdge);
       foreach($pageDecoded as $key =&gt; $member)
       {
           $id = $member-&gt;id;
       } 
      }
  }catch (Facebook\Exceptions\FacebookResponseException $e) {  echo 'Graph returned an error: ' . $e-&gt;getMessage(); }
  </code></pre>
  
  <p>It works for groups with few hundreads of people (even once for a group with 10.000 members) but randomly I'm occurring to this.</p>