Latest versions of WP and your theme installed. I have set the action to be display widget after clicking on Add to Cart, however nothing is being displayed.
Please insert the site admin access into the Private content below the message area. We will take a closer look at the case.
Please, confirm the permission for plugins deactivation, and switching to the parent theme. As soon as we complete the testing we will enable all back, however, the site would be without plugins for 15-20 min. You would better make the full backup of your site.
if you want to add the product to the cart from the, you need to enable “Quick shop” for variable products” in the Theme Settings > Shop > Variable product. https://gyazo.com/65f69d35f4adfabcd357e12e6abc4cc1
If you have any questions please feel free to contact us.