I started to add and remove songs from several playlist. Now HomePod says it can't play that playlist and wants me to try again later. Other times it says, it can't find that playlist or it says it will play but nothing plays. Even after you see the Siri graphic on top swirling to process the command...nothing plays. So adding or removing and renaming playlist screws up the whole thing. Maybe I'll just a few hours to see if iTunes Match finishes updating on the server. Perhaps thats what is causing it to fail again.