I switched my account settings (1) a couple of months ago, as I was using it with Facebook before and had someone from Spotify help me recover my email address and playlists. It seems like ever since this change, my Discover Weekly (3) and Release (4) Radar playlists have not been updating on my devices (2).
So far I have tried following without a solution:
Logging out and logging back in
Logging out, deinstalling and reinstalling
I was using Premium as an invitee from a Premium family account. Now I own a Premium family account.
iMac, 10.13.4 OSX with 184.108.40.2064.gef6b503e Spotify
MacBook Pro, 10.13.4 OSX with 220.127.116.114.gef6b503e Spotify