Thank you very much for choosing our theme and for contacting us.
Please provide your site admin access to the private area.
Please confirm the permit for us to deactivate the plugins not related to the theme and switch to the parent theme for the while of checking what may take up to 15 minutes. Please make the full backup of your site.
The problems was fixed by deactivating Siteground Caching problem. But We have another problem. When we click variation, it doesn’t change the image of the gallery.
I just recognized that this issue occurs for the products has more than one attribute option. Please see the link. Such as color and set. If it has only color either set, it works properly.