Playlist Thumbnail

I created a playlist in Apple Music and checked the box "Publish on profile and in search". The thumbnail for the playlist showed the first 4 LP covers from the songs on the playlist, as I desired, and when I went back and changed the title of the playlist it was still was fine. However, now when I copy/paste the Share Playlist link into Facebook the thumbnail does not show, and instead it is a closeup of the Apple Music Logo. I realize that this is not Facebook help forum, but by chance does anyone know if it's possible to force the thumbnail preview to show the same one that I see on Apple Music? Or what changed in the playlist so the default thumbnail preview does not show in other apps? Thanks!