Restoring Music Playlists

A few weeks ago all my music playlists were doubled by the same folders and playlists but without content.

Yesterday I updated my Mac to the latest MacOS Big Sur and decided to clean my music playlists by deleting these double folders and playlists without content. To be consternation I noticed that a few hours later all original folders and playlists with songs had also disappeared from my Music Playlist overview.

Any advice how I can restore all original music folders and playlists that I had until yesterday, before updating to the new operating system MacOS Big Sur and deleting the double music folders and playlists? I read that Apple keeps copies of your latest music library, folders and playlists when you update to a new MacOS operating system.

Grateful for your advice and support,

Best regards,

wdc