How to redirect using $this-session-userdata(country_territory)

Move this line from controller to view:

PHP Code:

$user_id = $this->session->userdata('user_id'); 


Or put the $user_id in an array which is passed to the view.
Controller:

PHP Code:

$data['user_id'] =  $this->session->userdata('user_id'); 
$this->load->view('createadvert', $data); 


In both cases, the $user_id variable will be available in the view.