public function check_postcode()
 {
     $customer = new WCPBC_Customer();
     $customer->save_data();
     $customer_data = WC()->session->get('wcpbc_customer');
     if (is_array($customer_data) && !empty($customer_data) && isset($customer_data['message'])) {
         return $customer_data['message'];
     } else {
         return false;
     }
 }