Only homepage can be translated?

Hello there,
The home page link contains /en/ or /hu/ for the second language. However, after you switch to Hungarian, then it works well on the homepage, I go to the shop then:
1. it goes back to English,
2. if I press on the Hungarian flag so that it would change the language, basically nothing changes, there is neither /en/ nor /hu/ in the URL and the language doesn’t change, it feels more like that the only page I can translate is the home page.

I’d appreciate it if I could receive some help regarding this topic, thank you in advance!

The page I need help with: [log in to see the link]