WRONG product added to cart

Hi,

In the "Price & enrollment" tab of your product page, you have a hikashop products listing module with add to cart buttons. That conflicts with the main add to cart button of the product page and it's a product from the listing module which is added to the cart instead of the main product of the page.
That's because the add to cart button form covers the whole product page, and you cannot have forms into other forms in HTML.

To avoid that, either deactivate the add to cart buttons of the products listing module inside the description or remove the module from the description and enable that module in the "modules under the product page" option of the configuration so that it displays below the product page and not inside it.