Assuming that you do not already have a Sonos system, having now gone onto factory reset your ‘used’ speaker, with its status LED (hopefully) now flashing green,  you need to first reset the Sonos App ‘Settings/App Preferences’ and on reopening the App, accept the T&C’s and go onto create a new Sonos system and setup/log onto your Sonos account and follow the onscreen instructions to setup your speaker.

Ensure that your mobile device and local network also meet the requirements shown in these two links below:

https://support.sonos.com/en-us/article/sonos-system-requirements

https://support.sonos.com/en-us/article/sonos-app-requirements

I checked your profile and it appears you already own multiple Sonos products so I must assume you already have a registered system. That said after you delete and reinstall the Sonos app as suggested rather than create a new system I’d select join an existing system.

If you are still having issues with your email look closely at what you are typing as it appears your registered Sonos e-mail doesn’t match what you are trying to enter.

Another possibility is there could be an issue with the Sonos server. I couldn’t log into the community a few minutes ago from the website. I had to click on an email update for another thread in order to get in. Go figure???

EDIT: With the number of Sonos products you own it’s unusual you only just joined the community on 10/4/23 with a first time issue. Are you the original owner of the system or have you already changed your account settings and are still trying to use old credentials?

I am experiencing the same "Sonos is currently registered to n...n@blabla.com

To finish registering your system, please enter the full email address below"

After completing the address it tells me to check my internet settings and try again.

Tried factory reset of product, tried resettimg the app, tried restarting the router... Followed the instructions given, and this just yoeldielded the same results.

​​​​​Any other ideas? 

Edit: I've had this product 5 years , and it has worked before, but I haven't bothered adding it to the Wifi since changing internet provider.

Spoke to support, and long story short, what solved the issue for me was to factory reset my system (while connected w/ LAN cable), reset app, wait for system to blink green, start app, register user, register system, enable wifi in app (can't use Wifi while connected to LAN), remove cable and then enter Wifi credentials… Voíla!

Hope this helps.

Thanks so much.  All fixed.  Reset app again and got closer to router, as I was on edge of my reception.

Brent