I have recently spent over an hour and a half on the phone with Sonos with the following issues that could not be solved.
RADIO
When I say "Alexa, play radio 4", Alexa says, "Playing BBC radio 4", then I hear the "BBC Sounds" intro, then Alexa says "Sorry, I'm having trouble. Please try in a little while."
MUSIC
When I say "Alexa, play music by queen", Alex replies, "Here's some music by Queen", then says, "Sorry, that device is offline". This happens with all devices.
We did everything under the sun with regards to router, Sonos speakers, system settings, account linking, voice assistant, powering down etc. They were brilliant but we could not solve it.
I have a Sonos system with the following devices. Boost, Beam, Roam, 3 x One. All using the same Amazon Music account which is the family unlimited.
I eventually found a solution through a forum telling me to go to alexa.amazon.co.uk to disable and reenable the Sonos skill online instead of on the Alexa phone app. I did that on alexa.amazon.co.uk instead of the Alexa app on my phone and it worked. Then it stopped again and I found unfortunately that the tab for working with skills had gone from alexa.amazon.co.uk and so I was unable to do the same again. They are winding down this online interface. Today I found that I could go into my amazon account another way and disable and reenable the Sonos skill. You go into the regular place you go to shop in your Amazon account, then there is a grey drop-down in the left side of search bar. You can select Alexa Skills in there. I disabled and reenabled the Sonos Skill (and incidentally my Sugarmate Skill) there. That worked. For now….