payment method - Opencart 1.5.6.4 : COD orders jumps to missing orders -

i've read other threads missing orders, makes different i'm using "free checkout" , "cash on delivery" payment methods, don't need make external call payment processor. i've checked think of , can't seem figure out. i've been using opencart 1.5x while no issues.

do have 'confirm' function in catalog/controller/payment/cod.php?

class controllerpaymentcod extends controller { protected function index() {     $this->data['button_confirm'] = $this->language->get('button_confirm');      $this->data['continue'] = $this->url->link('checkout/success');      if (file_exists(dir_template . $this->config->get('config_template') . '/template/payment/cod.tpl')) {         $this->template = $this->config->get('config_template') . '/template/payment/cod.tpl';     } else {         $this->template = 'default/template/payment/cod.tpl';     }      $this->render(); }  public function confirm() {     $this->load->model('checkout/order');      $this->model_checkout_order->confirm($this->session->data['order_id'], $this->config->get('cod_order_status_id'), '', true); } }