Factory reset your primary point and all other points
- Open the Google Wifi app .
- Tap Settings and actions tab Network & general.
- Under “Network,” tap Wifi point(s).
- Tap Factory Reset.
- The Wifi point(s) will flash blue, then turn solid blue.
How to Factory Reset a Google WiFi
Key points: Use the Google Wi-Fi App, Hardware Switch, Reset Switch, Factory Reset the Device
Source: https://support.google.com/googlenest/answer/6246619?hl=en