Apple Music users can sync libraries across devices by enabling a specific setting
Users of Apple Music can now ensure their music libraries appear on all connected devices by turning on the Sync Library feature.

Account verification required first
The primary reason for unsynced libraries is often the use of different accounts on each device. Users must check that the email address displayed in the Apple Music app matches their primary account before proceeding.
Enable setting on iPhone and iPad
To fix the issue, open Settings and locate the Apps list to find the Music application. Tapping this entry allows users to enable the Sync Library option directly within the app settings.
Process works for other platforms too
The service is available on Android phones, Windows PCs, and smart TVs alongside Apple hardware. Signing in with the correct account ensures songs appear on these various operating systems without manual management.
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