Playlists missing from Windows app, but show in Android

[alg2]

Plan

Premium Family

Country

 USA 

Device

Dell PC ~2016 vintage

Operating System

Windows 10

My Question or Issue

I have a lot of playlists.  I organize them into folders, and subfolders, and sub-sub-folders, alphabetically.  e.g.  "ABC" --> "A" --> "AC/DC"  --> "Back in Black" and so forth.  I noticed that on Windows native Spotify app the playlists towards the bottom of my list - "STU" and "WXYZ" - were missing (e.g. "WXYZ" is there, but "W" and all its sub-folders and playlists are missing).  

I notice that on Android, all the playlists are there, so its not that I accidentally deleted them.  I went to the Web page to restore deleted playlists, and as expected, they are not on the deleted list, because I didn't delete them!

Yet, they are missing from the Windows player.  They were gone for a day.

And then, magically, they re-appeared in the Windows player!

You got a bug somewhere in your app folks...