Hey guys...
My Echo 4th was also being difficult, and I did everything, yall mentioned, too! Nothing! I finally got it working just by changing the name of my playlists, mostly just adding 'my' to the Name of the Playlist. I have one called nursery...and added 'my' and it worked.... I don't question it...I'm just glad it's back. Change the names, it really worked. I know most of us say "my" before we state Playlist...but putting that Into the Playlist Name...just worked. By the way...use the Amazon Music App to Edit Playlists Name. Hope this helps.