A few days ago my Nest legacy products like Nest Hello, Nest Cam IQ and Nest Connect will no longer connect to wifi after being connected to wifi for 5+ years.
I've tried resetting Nest app, deleting and resetting up the products.
The app fails every time to connect the devices to wifi or it sets them up and then about 5 min after connection they show up in the Nest app and Home app as "not connected"
I'm running 3 Google Wifi routers all hard wired to ATT Fiber and pulling 800mbps up & down.
Why does Google constantly break things with firmware and software updates.
This is something that I'm pretty sure you need to speak with a Google Nest Tech on the phone. Here is the link to open and support ticket and there will be an option to start a phone call. I believe they are there 24/7.
Good luck and please return here and let us know how this turned out. It might help other folks running into the same or similar problem