iOS 18 update empties old playlists in Apple Music

All my old curated playlists are empty . I had created a playlist for all songs on my iPhone 3 years ago. Everything is empty now. At first, after the update, Apple Music suddenly behaved strangely. It showed no

option to download new songs or add them to playlists . It showed me a syncing … bar on top. Once I synced it up with my mac, I could see options to download new songs and add them to existing playlists or create new playlists . But my issue is with the old playlists being empty . Those songs are impossible to get back . Could you please help. I have not changed any sync settings ever.

[Re-Titled by Moderator]