Sessions not working on CI 3

Hi;

I create session manually and it works fine locally but not when I upload it to server. Can anyone see what I am doing wrong?

'Thanks

Creating session in controller

PHP Code:

if($_POST)
 {
 if((strlen($_POST['comment'])>2) && ($_POST['secret']==5))
 {
 $data = array(
   'comment' => $_POST['comment'],
   'page_id' => $this->data['id'],
   'email' => $_POST['email'],
   'date_added' => date('Y-m-d')
 );
 $this->db->insert('breakup_comments', $data);
 $_SESSION['comment_added'] = '<strong class = "green">Your comment has been added successfully! It will appear in a couple hours :)</strong><br /><br />';
 redirect($this->data['return_path'], 'refresh');
 }
} 


Viewing..well trying to

PHP Code:

if(isset($_SESSION['comment_added']))
              {
                if(strlen($_SESSION['comment_added'])>3)
                  {
                    echo $_SESSION['comment_added'];
                    $_SESSION['comment_added'] = "";
                  }  
              }