Hi. Here are some 404 Errors and Warnings I get from your site.
1. 404 error from Demo link here: https://www.techfry.com/joomla-extensions/shopping-cart-for-joomla
2. Multiple Warnings from Add to Cart button on TF Shop demos here: https://joomla.techfry.com/tf-shop-demo
Thank you for informing about the issues. We are working to solve these.