ทำระบบ Facebook Login PHP SDK ดึงข้อมูลได้หลายอย่าง แต่ะดึงอีเมล์ (Email Address) ไม่ได้

// Create our Application instance (replace this with your appId and secret).
$facebook = new Facebook(array(
  'appId'  => 'xxxxx',
  'secret' => 'xxxxxx',
  'cookie' => true
));

// Get User ID
$user = $facebook->getUser();

// We may or may not have this data based on whether the user is logged in.
//
// If we have a $user id here, it means we know the user is logged into
// Facebook, but we don't know if the access token is valid. An access
// token is invalid if the user logged out of Facebook.

if ($user) {
  try {
    // Proceed knowing you have a logged in user who's authenticated.
    $user_profile = $facebook->api('/me');
  } catch (FacebookApiException $e) {
    error_log($e);
    $user = null;
   echo 'Caught exception: ',  $e->getMessage(), "\n";
  }
}

// Login or logout url will be needed depending on current user state.
if ($user) {
  $logoutUrl = $facebook->getLogoutUrl();
} else {
  $loginUrl = $facebook->getLoginUrl();
}

// This call will always work since we are fetching public data.
$naitik = $facebook->api('/naitik');


   $fb_id =$user_profile['id'];
   $dealmember_fbid = $user_profile['id'];
   $fb_name =$user_profile['name'];
   $fb_first_name =$user_profile['first_name'];
   $fb_last_name =$user_profile['last_name'];
   $fb_link =$user_profile['link'];
   $fb_username =$user_profile['username'];
   $fb_gender =$user_profile['gender'];
   $contact_email = $user_profile["contact_email"];     //this was a separate permission, remember?
   $email = $user_profile["email"];     //this was a separate permission, remember?
   
   echo " fb_id = $fb_id <br>";
   echo " dealmember_fbid = $dealmember_fbid <br>";
   echo " fb_name = $fb_name <br>";
   echo " fb_first_name = $fb_first_name <br>";
   echo " fb_last_name = $fb_last_name <br>";
   echo " fb_link = $fb_link <br>";
   echo " fb_username = $fb_username <br>";
   echo " contact_email = $contact_email <br>";
   echo " email = $email <br>";