Hi Ismael

I have no extensions, only Woocommerce. Everything is the “default” exactly as it was automatically installed by WooCommerce. I haven’t even changed any of the pages the only thing I added is the Test Product.

The add to cart that isn’t working is the one in the product page and it happens ONLY if you are new to the website. If you already used the add to cart on the shop page, it will work.

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So to reset yourself to a “NEW” status you need to clear your cookies and then start over fresh with an empty cart and immediately go into the product details page and click add to cart there instead of the shop.