login with facebook CodeIgniter not working

<?php
ini_set("display_errors","1");
class Home extends CI_Controller
{
    function __construct()
    {
        parent::__construct();
        
        $this->load->model('Facebook_model');
 $this->load->library('session');
    }
    function index()
    {
        $fb_data = $this->session->userdata('fb_data'); 
        
         if((!$fb_data['uid']) or (!$fb_data['me']))
        {
            // If this is a protected section that needs user authentication
            // you can redirect the user somewhere else
            // or take any other action you need
            redirect('login');
        }
        else
        {
            $data = array(
                    'fb_data' => $fb_data,
                    );
 
            $this->load->view('home', $data);
        }
    }
}



?>

<?php

class Facebook_model extends CI_Model
{
    public function __construct()
    {
        parent::__construct();
        $config=array(
         'appId'  => '828846557141612',
                        'secret' => '7913e12f9a5d746f10a35c5c176cce42',
                        'fileUpload' => true, // Indicates if the CURL
        
        
        
        
        );
        
       

        
        $this->load->library('Facebook',$config);
        $user=$this->facebook->getUser();
         $profile = null;
         
         if($user)
         {
            try
            {
              $profile=$this->facebook->api('/me?fields=id,name,link,email');
              
              
              
            }
            catch(FacebookApiException $e)
            {
                error_log($e);
                $user = null;
            }
         }
         $fb_data=array(
         
                'me' => $profile,
                        'uid' => $user,
                        'loginUrl' => $this->facebook->getLoginUrl(
                            array(
                                'scope' => 'email,user_birthday,publish_stream', // app permissions
                                'redirect_uri' => 'http://tawrny.com/demo/jobs/' // URL where you want to redirect your users after 
                            )
                        ),
                        'logoutUrl' => $this->facebook->getLogoutUrl(),
         
         
         );
         
         
          $this->session->set_userdata('fb_data', $fb_data);
         
         
         
         
         
    }
    
}


?>

<?php if(!$fb_data['me']): ?>
  Please login with your FB account: <a href="<?php echo $fb_data['loginUrl']; ?>">login</a>
  <!-- Or you can use XFBML -->
<div class="fb-login-button" data-show-faces="false" data-width="100" data-max-rows="1" data-scope="email,user_birthday,publish_stream"></div>
  <?php else: ?>
  <img class="pic" alt="" src="https://graph.facebook.com/<?php echo $fb_data['uid']; ?>/picture" />

Hi <?php echo $fb_data['me']['name']; ?>,

    <a href="<?php echo site_url('topsecret'); ?>">You can access the top secret page</a> or <a href="<?php echo $fb_data['logoutUrl']; ?>">logout</a>

  <?php endif; ?>

This webpage has a redirect loop