Wife can no longer play her playlists through Amazon devices

We have music unlimited. I am primary account, wife is part of family grouping. We have several echo and Amazon devices. My wife creates playlists on the fly through those various devices. She has always been able to play them on any of the devices. All of a sudden when she asks for alexa to play one of her list, the reply is "cannot find the named Playlist." Weird thing, if I ask for the playlist it works fine. She has a voice registration with her Amazon app. This just started happening last week. Prior, it worked fine. I can't figure out via my app or hers what is wrong?? Any help would be appreciated.