Experienced wordpress and woocommerce coder

I am running into some issues with a website running on wordpress and using the woocommerce plugin. this is for a website to sell clothes so the items require to have a dropdown with "size" feature. for some reason the button "add to cart" is not appearing. this might be either a theme or a woocommerce issue. i need someone to login to the admin panel and check into this issue and offer recommendations.