Functions don't work

I just purchased the premium version of generate press, however I am having difficulties. When I try to change the font weight on the h1 tags it changes on the preview but not on the site although I have published. When I change the content padding in layouts, it also changes on the preview but not on the actual site in spite of saving. I also tried to add this to css to change to 3 products per row but nothing happens

.woocommerce ul.products li.product,
.woocommerce-page ul.products li.product {
float: left;
margin: 0 3% 2.992em 0;
width: 30%;
}

What is up?
Thank you