@Lomelimari Sorry for the trouble.
You should be able to use the Shuffle feature when sorting your collection by Stations or Songs.
If you are not seeing this option, can you explain your issue a bit further?
To clarify, are you having issues shuffling your collected stations?
Additionally you listening to Pandora on a computer or on a device?
The more details you're able to provide, the better equipped I'll be to help.
I look forward to hearing back.