Get local files to show up in iOS app

[Claramai]

I have read almost all the posts in here and have tried everything from reinstalling the apps to import local files again.

The playlist shows up on my phone, but with no content. The only time I received a response was when I created a local network from my phone. Then I got a message saying: "Sync song to this phone". Step 3 says: "Mark the playlist containing this song for Offline Sync on your coputer or on this phone".

I have absolutely no idea, how to find "Offline Sync" on web or app? All the songs are downloaded and work in the web app.

Details:

Premium

Denmark

iOS 10XS

iOS 12.3.1

Mac