Some of my products from my list are capable to be added to cart but some of them are cannot add even it reloaded after you clicked the add to cart button. It only happens, under one of my categories. But when you visit the cart after you click the add to cart button and the page reloaded, a Magento alert pop-up and it says that the product is now added.
How can I resolve this delay issue?
I already cleared cache both Magento and browser, Increase the session time limit, disable varnish but nothing worked.
Thanks for the help in advance
