Some Apple users are reporting issues syncing their Apple Music library between their iPhone and Mac.
Affected users receive the following error message in the Music app on the Mac:
Genius results can’t be updated right now. An unknown error occurred (18004).
Users are complaining about the issue on the Apple Support Community, MacRumors Forums, Reddit, and elsewhere.
Reddit user re-claimed said:
For the past few weeks, I and a lot of other people have been unable to sync their iCloud Music Library to any of their devices. On the Mac, the library doesn’t sync at all and gives an error 18004. On iOS, iPadOS, tvOS and watchOS, the Apple Music app only shows purchased music from the iTunes Store but nothing from Apple Music.
The library can still be accessed on music.apple.com so it’s not completely lost. However, if you still have your library syncing on one device and you disable and enable the library again, you’ll probably lose access to it.
The underlying cause of the issue is currently unknown, and it’s not entirely clear if a software update will fix the issue, or if Apple can implement a server-side fix. Apple has yet to comment on the issue, and we’ll update this space if we learn more about the issue.