The shipping address information disapears, after adding promo code in checkout form.

[quarkpol]

The shipping address information disapear, after adding promo code in checkout form.

Steps to reproduce the problem

1. Add products to cart
2. Click checkout
3. complete shipping address form
4. Add promo code

-- Filled shipping address informations disappear

What I expected to happen

The completed form with shipping informations remain filled after adding promo code.

[Pacu2]

We could send the promo code asynchronously, so data filled in forms would remain untouched.