Thanks for the topic.You will happy to know that, this is not our plugin issue. This is happening because you haven’t set your product properly. You have allowed your product to be sold only individually. That means customer can purchase only one product at a time. And you’ve done it from the product configuration . See here https://prntscr.com/nu8ly1 . You should uncheck it if you want to sell more than 1 product at a time. Look here https://prntscr.com/nu8ofc , I have added 3 products.
You said you can’t update cart. The cart page is not related to our plugin. It’s woocommerce default page so you should have thought that the error is may not related to Woo Product Table Pro plugin.
I hope you are clear now.
Thanks