When I download album to be available in offline mode they stay offline for a few days/Weeks (the green arrow says it's there) but Eventually They won't be available offline a few week later, the green arrow desapear and I can't play them if not connected to Cell or Wifi... But the point is they still use space on my phone's storage... Log out Log in doesn't fix anything.
Playlist Doesn't seems to be affected, only Albums in my music
So I have to uninstall spotify app eachtime it happens to get the diskspace back and reinstall and redownload every thing.... !!!!