I just wanted to say I am having this same issue. I can not browse my song, playlist nothing from my radio.I have tried uninstalling and reinstalling spotify a few times along with the kenwood app and no change at all. I noticed that I get that screen that says someing about safe driving and I used to never get that screen could that be part of the proble.
Hi I've been having the same issue since January 24th.
I've reset my head unit and updated the firmware and uninstalled and reinstalled the Spotify app and the issue has persisted. I'm on Spotify version 22.214.171.1249, running Android 9 on the Pixel 3 (last updated this morning with the February 5th security patch level), on a Kenwood ddx9703s.