Problem With the stockable product

I have a problem when I use the plugin virtuemart "stockable product", to manage inventory and product variants, to the left of the button "add to cart" appear two empty square, depends on what? how can I fix it? thanks

Could you please check if they are visible also on default beeze template?

With breeze the problem not show! do you have an idea for resolve the problem? or another method for manage the quantity and variant of product?thanks

Could You please post an url to your site where I can check this pbolem?