alexa stops working on era100 cosrantly

That’s unusual, certainly. I’d guess some potential for an ongoing connection to the Amazon servers, but it isn’t clear why. I’d certainly try a network refresh, by powering / unplugging all Sonos devices, then performing a reboot of your router. Wait two minutes, then plugging back in your Sonos devices. Wait another two minutes before your initial test, then try the next day, and see if it works.

If it doesn’t, I would recommend that you submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. Don’t post the resulting diagnostic number here.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

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