How can I make the checkout process multilingual on Yanka theme?

Hi! Just bought a new theme because the first one had really some issues which bugged us so now we are using the Yanka theme. In the demo pages everything looks like we need it, but somehow we can‘t make the checkout multilingual - we have english as default language and translated to hungarian and slovak as well, used the TLab AI to translate our shop. Everything looks fine to us but the checkout redirects to the native english language somehow, we have found the „routes“ liquid object on the shopify.dev site but i don‘t understand how or where should we add something?
rvprintshop.com is our site, if somebody could help would be really great! Thanks