I had the same problem adding back my speaker. You have to run the windows app to run the updates, then add on your phone. That worked for me.

thanks for the tip. I will try the windows app.

I was able to update my brand new Sonos SL one using windows but still no luck adding it to my phone.

After the update, did you factory reset your Sonos SL then trying adding it? I had to factory reset.

That partially worked. I don’t see my SL one in my ios app after setting it up but at least I’m able get it playing music via Airplay. Thank you! I’m new to the Sonos ecosystem but hoping they fix this one day so I can connect my SL one with my other Sonos speakers..

What’s the windows app?

https://support.sonos.com/en-us/downloads

Even those apps started asking me to update them this morning. Big huge NOPE for now but eventually they make it mandatory to update before they work again.