Lost most of my music on PC - using Apple Music

Most of my playlists have either disappeared completely or the content of the playlist is gone on my PC 😟 I'm using Apple Music, all of the Apple Music is gone, everything I have added via CD is gone all and a lot of what I purchased on iTunes is gone. After spending a couple hours with Apple Music Support, nobody seems to know what has happened. All of the playlists and music are still on my iPhone, so that's good. Anyone have this happen before? My computer did crash a week before I lost the music, so don't know if that's related (I did have all my music for 5 days after the crash) and Windows is not activated on my new hard drive (that's another story) again don't know if that would matter. Any help would be much appreciated. Thanks!