Playlists have disappeared

Sometime in that past few days all of my playlists have disappeared. No updates applied but I did not notice that a recent rescan did the whole library. Has something wiped it out?

The playlist folder setting looks ok = /storage/music/playlist (Linux) and the .m3u files are there but the folder looks empty via the LMS interface.

I've tried creating a new folder with a copy of the playlists, changed the settings to match and restarted LMS but no joy .

LMS V7.8.0

Thanks