I followed this guide:
After entering the information needed, I am redirected to the Spotify site:
And see the above message in the subject line above in the browser window.
Maybe the info is outdated?
I was also trying the Spotify Connect plugin as a device along with a Google AIY I have installed on a Raspberry Pi 3B. That is sort of working, but I cannot figure out how to increase the device volume. When I try on a Spotify app, I can only hear when I put the volume at maximum, but it sounds over driven and distorted.