iTunes Match / Music app

When you first sign up for iTunes Match and enable Sync Library on your computer Music will scan your library and attempt to match all of your music with corresponding items in the store, or upload your tracks where no match is found. Depending on the size of your library this can take some time, however it is also possible that the process has stalled. See Identify cloud status icons in your music library on your Mac or PC - Apple Support to review the status of your tracks. Those that are waiting have yet to be processed. You may need to force quit Music and/or your Mac, then restart to resume the matching of your library. Where tracks aren't matched, uploaded, or purchased you can try right-click > Add to (Cloud) Library to force them to be processed, and you can use the File > Library > Update Cloud Library to resume the syncing of your library to the cloud if it hasn't happened automatically.

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Playlists that contain ineligible content, won't be added to iCloud Music Library. There should be an icon alongside the playlist name to indicate this. (See Identify cloud status icons in your music library on your Mac or PC - Apple Support). You could try right-clicking a playlist name and seeing if Add to (Cloud) Library is available in the same way that it works with tracks.

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