woocommerce中的结帐表单不会重定向到外部链接

I searched all day but found nothing.

Checkout form in form-checkout.php (woocommerce) normally is submitted to checkout page again if there is missing area or order-received page if everything is OK.

I changed the form action in form-checkout.php like this :

<form action = "https://virtual pos site link of my bank">

However, when i submit the form, woocommerce's own ajax runs and goes to order-received page not bank site.

I tried in checkout page with javascript :

preventDefault() , stopPropagation() 

but did not worked.

Is there any way to prevent custom ajax/javascript events in that page and enable to submit external bank site link?