title: The request is invalid because the app secret is the same as the client token
body: <p>My Facebook app was working fine yesterday, but today it does not work for getting access_token.</p>
  
  <p>My code is:</p>
  
  <pre><code>$token_url="https://graph.facebook.com/oauth/access_token?"."client_id=".$app_id."&amp;redirect_uri=".urlencode($my_url)."&amp;client_secret=".$app_secret."&amp;code=".$code;
  $response=file_get_contents($token_url);
  print_r($response);
  $params = null;
  parse_str($response, $params);
  echo  $params['access_token'];
  </code></pre>
  
  <p>The error is:</p>
  
  <pre><code>{
     "error": {
        "message": "The request is invalid because the app secret is the same as the client token",
        "type": "OAuthException",
        "code": 1
     }
  }
  </code></pre>
  
  <p>How to solve this issue?</p>
  
  <p>I also used curl, but the response is:</p>
  
  <pre><code>object(stdClass)#121 (1) {
      ["error"]=&gt; object(stdClass)#11 (3) {
          ["message"]=&gt; string(77) "The request is invalid because the app secret is the same as the client token"
          ["type"]=&gt; string(14) "OAuthException"
          ["code"]=&gt; int(1)
      }
  } 
  </code></pre>