Public share - filenames / foldernames invisible by mobile

if I access a pblic share with any mobile device (any app), I cant see any filename / foldername. Only an icon (folder / video f.e.) and two letters of the file-extension (.mp).

I can switch to Desktopview in the app - doesnt work. If I login with my account I can see all the filenames / foldernames, size, … . It only happens with public shares.

It is installed NC 17.0.3. Unfortunately I dont have access to servers logfile. But because I can see everything if I am logged in, it should not be a serverside problem.

Thanks for youre help!