In most reported cases, in the Amazon and Alexa And Sonos area of this forum, the issue appears to be resolved. Since Sonos didn’t release anything, I’d take the assumption that the issue was on Amazon’s servers. If you’re still experiencing an issue, I’d encourage you to do a few things. First, try rebooting your speakers and your router. Then, call Sonos Support directly to discuss it.

When you speak directly to the phone folks, they have tools at their disposal that will allow them to give you advice specific to your Sonos system and network. 

Thanks. I rang support in the end and now sorted.