Multilanguage property page

I’m using Polyland for language switcher. When I’m, for example, on English and I go to page https://nekretninecentar.rs/en/two-room-apartments/ and want to se some property and click on it it returns me on serbian view. Main permalink is set for https://nekretninecentar.rs/stanovi/ is this option only for PRO users or am I doing something wrong.

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