Fb call back

<?php
require_once 'Facebook/autoload.php';


session_start();
$accessToken = 'EAAgYqiZABgdIBAAGVBStzrB4HxzN8fP5JQgmoQQAygGwVjlrqzZBCR6kXETlZC8TiIR1K5InvbZBhwYChpRSmziL3O7bmRR6VkU0vb5NdYZAjoL2GYWTjhzOZBQ8TUytC6dyvuyn6xZBX2dhx21B7TrZBdsZBzyUqwHMZCG8AFs4l1CgZDZD';
$fb = new Facebook\Facebook([
  'app_id' => '2278918879019474', // Replace {app-id} with your app id
  'app_secret' => 'ff014e818418e45b1835791a8f6f11de',
  'default_graph_version' => 'v3.2',
  ]);

$helper = $fb->getRedirectLoginHelper();
if (isset($_GET['state'])){
  $helper ->getPersistentDataHandler()->set('state', $_GET['state']);
}

try {
  // Returns a `FacebookFacebookResponse` object
  $response = $fb->get(
    '/267445520817200_275171656711253/comments/?fields=from,created_time,message&limit=100',
    $accessToken
  );
} catch(FacebookExceptionsFacebookResponseException $e) {
  echo 'Graph returned an error: ' . $e->getMessage();
  exit;
} catch(FacebookExceptionsFacebookSDKException $e) {
  echo 'Facebook SDK returned an error: ' . $e->getMessage();
  exit;
}
$graphEdge = $response->getGraphEdge();

$user=$response->getGraphEdge();
echo "<pre>";
print_r($user);

echo $user['from'].'</br>';
echo $user['created_time'].'</br>';
echo $user['message'].'</br>';

?>