[Web Player][Playlists] "Failed to save changes, please try again."

[Cloud1]

Hi all, in trying to make a new playlist for Halloween, I keep getting a message in red saying: "Failed to save changes, please try again," and no matter WHAT I do, it doesn't do anything or save and create the playlist, please help, I need to make this playlist. 

I am running on Mac OS Mojave, version 10.14.6 Macbook Air mid 2013.