Refresh problem

Here is the problem I found. I read about a similar problem in the forum but I think I can make you understand the situation better.

Well the plugin works fine if you have data for all the payment methods.
I will make an example just to understand the update problem.
Lets say we have 2 payment methods the method A and method B
Now for method A I write a 10% discount and for B I just write 0

On checkout I select the method A and I get the 10% but after that I change my mind and want to select method B then the discount is removed but the data in total section is not refreshed. If I refresh the page manually the numbers are corrected.

Now if I have a discount in both payment methods the page refresh perfectly fine.

I even tried to give a 0% discount but it did not work ether.

Also when I select something the page scrolls to top to inform you that a coupon is added. Can we stop this page scrolling? I am trying to pay and leave and I have to see all the page from he beginning

Thanks in advance