I’m having the same issue.  Spotify works through Sonos the amazon music app works on my phone, but AM through the Sonos keeps throwing the dreaded requested operation failed message.  

same issue here

Same issue here in the US tried removing and reconnecting Amazon unlimited app plus making sure my individual plan was not shared with my family and I still get the message. Music plays from the app itself no issues but not through Sonos app

Just received the message that AM is experiencing a full outage. Plays fine on my iPhone and iPad.

Hi folks, Thank you for reaching out, and welcome to the community. Amazon Music is currently experiencing a service outage for playback failure. We are working with our team to have this issue be fixed as soon as possible. You can check on the status of the outage from our website status.sonos.com for updates once it has been fixed.

Please, feel free to let us know if you require any further information.

The Sonos community is always here to help. 

Thanks for the info.

As a temporary fix, Amazon Music App plays on SONOS using AirPlay.

AM seems to be playing fine now. Thanks Sonos Staff.

Hi folks, Amazon Music’s service outage for playback failure is already fixed and resolved. for future reference, you may also go to our website status.sonos.com to check for any ongoing outage. If you have any questions or run into any other issues, please do not hesitate to contact us. We are always happy to assist you.

The Sonos community is always here to help.