Spotify is skipping every song

[user-removed]

I restared my Computer and now Spotify is skipping every song and says: "This Song is not aviable. If the song is on your Computer, you can import it." or "Current song can not be played"

I have the newest Windows 10 Spotify App via the Store
My Pc Drivers are up to date
Before I restared my Pc, I only played games and browsed the web.

What I tried:
Restart Pc
Restart Router
Reinstall Spotify
Tried another Sound output