Automatically add to cart bug

Hello,

I have the eCommerce Plus theme. And the WooCommerce plug in. But every time I add a product to my cart. And I go to my cart, it automatically adds the same product again. I tried other themes, but it only happens with eCommerce Plus. I reinstalled the theme multiple times and deactivated all my other plug ins, but it is still happening. Please help me, I don’t know what to do.

Kind regards