sync erased playlists

See Hide and unhide music, movies, TV shows, audiobooks, and books - Apple Support and Redownload apps, music, movies, TV shows, and books from the App Store, iTunes Store, and Apple Books - Apple Support and fetch any purchases directly from the iTunes Store.

Once everything is in your library set up your sync selections and sync what you want to the device.

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Are the playlists still in your library? If not see Empty/corrupt iTunes library after upgrade/crash - Apple Community, otherwise see Use iTunes to sync your iPhone, iPad, or iPod with your computer - Apple Support and set up your sync selections again.

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