Add to Cart button on Google Site opening PayPal main page
I am using Google Sites and have a PayPal Add to Cart button that works great except for one instance. We have the link to our site on our Facebook page. The user (on phone or tablet) opens that then clicks the "Add to Cart" and it does not go to the checkout, it goes to the main PayPal page. If they click "open in Safari" it works, but we don't want them to have to do that. Is there code to open it automatically in a web browser from the smart phone?