I am working on a Site which is http://www.casualcountryusa.com/, suddenly Quick Add to Card (shown below on every product) is stop workig and also the checkout page, Order Recipt is also showing in-process/busy … kindly take a look on this
Please deactivate all the plugins not related to the theme and switch the parent theme, check the issue, If the problem has gone, activate the plugins one by one, checking the issue to detect which one causes the problem.
if the problem remains, even after the plugins deactivated leave the plugins deactivated for us to check and provide your site admin access to the private area.