Product Table in MultiStep Checkout

Hello, I am using WooCommerce MultiStep Checkout Wizard with Product Table Lite in order to create a step where customers are offered “add-on products” like utensil and place settings. I added two columns for quantity and a “Add to Cart” button using AJAX, respectively.

I can add products to the cart fine, but for some reason the quantity selector is preventing me from going to the next step. Here’s a screenshot. I haven’t found any error yet.

Is this an issue with my table’s setup, the Product Table Lite plugin itself, or the MultiStep Checkout Wizard plugin? Any help to shed light on this would be appreciated. Thank you!