This problem is usually encountered after problems with the internet connection. The problem is not a problem on the Spotify side. Try adjusting your DNS settings. Please try logging in again using Cloudflare DNS. Most likely your problem will be solved.
I tried that, it still shows the same error. Everything else that uses internet connection, like the PSN Store, Youtube, Prime Video, Netflix, is working as usual. The only app not working properly is Spotify.
Could you try the following - Go to settings > account management > Link with other services > turn it off for Spotify > restart your ps4 > log in.
If that doesn't help, can you try again by connecting your Playstation 4 to a different network? (Like turning on a hotspot on your phone.)
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