Hey @labia, welcome to the Sonos Community!
Sorry to hear you cannot listen to Rai Radio anymore on your Sonos. I’m based in the UK and experience the same issue. Also on other radio service providers Radio Rai seems unavailable.
On TuneIn’s website I get a message that the station is not available in my location, which indicates that it is geo-blocked and might really be only available in Italy. Only way to find out, is a field trip, but my boss wont fund my expenses I’m afraid 😅
Perhaps you have someone back home who can test for you or there is a Italy based user on the forum who can help?