Hey @neo_n2o89, thanks for reaching out to the Community!
Let's see what's going on.
Could you let me know what happens exactly when you try to add a song to your playlist? Screenshots/screen recordings can be very helpful making sure you hide sensitive info when posting to the Community.
Also, if possible try logging into your Spotify on a different device and see if you're able to add songs to your playlist from there.
Make sure that your app and your device is all up to date to the current software.
Perform another clean, thorough reinstall of the app following these steps.
Let me know how this goes!
Billy-JRock Star 22
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