Need to prevent iPad from deleting playlists when connected to desktop

After working great for over year, now when I connect the iPad to the desktop, instead of syncing the playlist, the iPad deletes the playlists from the desktop. I had backed up to a separate hard drive, and was able to restore (only lost two months of updates). Tried to sync a second time and again lost the playlists. Restored again from detachable hard drive, and synced the phone with no issue. Tried the iPad again, and lost the playlists again!

What is going on? Can I ever sync the iPad again?