Cannot Scroll on Page

I use your Modal Window popup on my Main page, SHOP page and on the two books page. However, when a customer click on the “Reviews” of either one of my books’s review. Whenever the customer click on the previous page; then my whole page just freeze. The page itself cannot scroll up nor down.

As of now I took off the modal pop on the individual books page. I only leave it on the home page and main shop page. However, I really would like to use it on the book page itself since the pop-up is really for the book audio sign-up.

Thanks!

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