Cant get "synonyms" to work for Google Assistant


i wanted to add some synonyms to my Items wich are exposed for Google Assistant.
GA ist synchronizing well after saving the new entries in the .items file. But i cannot access any of my items with the alternative names. Is there something wrong with my code?

Switch TV_schauen “TV-Wohnzimmer” { synonyms=“Fernseher”, ga=“Outlet”[ roomHint=“Wohnzimmer” ] }