Sorry no products matched your selection

Hi, I have developed a shopping page where a user can access all the products at once at http://dev3.wagnermeters.com/phone-shopping . The problem is in the variable products it does not show the options and add to cart button is disabled. I have removed the alert otherwise it just alert for every variable product on the page saying no products matched your selection. Please help me and thanks in advance.

https://wordpress.org/plugins/woocommerce/