Good morning,
on the website https://greenwallbox.pl/ there is a problem with Your theme and WPML String Translation plug-in. The situation occurs, for example, when trying to purchase the product Green Wallbox 2 Pro Slim 22kW (https://greenwallbox.pl/produkt/green-wallbox-2-pro-slim-22kw/?attribute_pa_dlugosc-kabla=6-metrow). When the “Extended warranty up to 5 years (+PLN 699.00)” option is selected in the PL language version, only the product itself is added to the cart – without the previously selected warranty. This problem does not occur on the EN version of the website – https://greenwallbox.com/produkt/green-wallbox-2-pro-slim-22kw/?attribute_pa_dlugosc-kabla=6-metrow
We contacted with WPML support and it turns out that there are no problems with the plugin itself, but with the theme. After changing the theme to Twenty twenty-one everything works fine. Can You check Yourself or give us the solution how to fix settings in Your theme so it can works properly with the plugin?