Hi @smiliniis, Welcome to the Community and thank you for your first post!
To keep things organized, I moved your original post to Desktop: Shuffle Button is Missing.
To shuffle as Pandora Premium user, go to My Collection, and sort the collection by Stations or songs and select Shuffle Stations/songs.
You should be able to shuffle your stations or songs through this method.
However, if you're still seeing the shuffle option greyed out, would you mind sending me a screen shot of what you're seeing and the web browser you're using (i.e Chrome, Firefox)?
Let me know if you're still having trouble and I can send you some troubleshooting instructions that we can try! 🎧