I have no idea why but you placed the eStore shortcode inside the following HTML code so you were forcing it to go to PayPal sandbox:
<form action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post">
I am guessing you had some plain PayPal button there before and you forgot to remove that button code. I removed it and now it goes to the live PayPal site.