Diagnosis
This is often caused by a conflict with an old router or access point that’s still active on your network. Your devices are remembering and trying to connect to the old network’s SSID (Wi-Fi name) which might now be broadcasting as your Guest network, or they’re getting confused by duplicate IP addresses.
How to Fix It
You need to make a clean break. First, ensure your old router is completely powered off and disconnected. Then, on your problem devices (phones, laptops), go into their Wi-Fi settings and “Forget” or delete the network profile for your *old* Wi-Fi name. Also, forget any network with a name similar to your new Nest Wifi network. Then, reconnect fresh by selecting your new primary Nest Wifi network and entering the password.
If That Didn't Work
There’s a feature called “Device Access” in the Google Home app that might be interfering. Go to your Wi-Fi settings in the app, then Advanced networking > Device Access. Make sure your personal devices aren’t listed under “Guest devices” or being paused/restricted by a schedule you might have set accidentally.
Heads Up
When you first set up the Nest Wifi Pro, it creates a primary network and a separate Guest network. The Guest network name is your main SSID with “-Guest” added. Double-check you’re not accidentally giving guests the primary password or connecting your own devices to the Guest SSID, as those connections are isolated and can feel “broken.”