If your device is still connected to an existing Wi-Fi network, you can follow these steps to change the Wi-Fi network it is connected to. See the "If your speaker or display is currently connected to a Wi-Fi network" section.
If you've already changed to a different Wi-Fi network, try these steps:
Instead of factory resetting your speaker or display, if you're comfortable changing your router settings, you can change your new Wi-Fi network name and password in your router's settings to be the same as the previous ones. Your device should then automatically connect to the Wi-Fi.
Thanks for the help, davidking. I appreciate it!
Mga, hope that helps, but if you're still having trouble connecting your Chromecast to the new network, please try to manually connect to the Chromecast SSID. Here's how: Go to the phone settings > Open Wi-Fi and connect to the Chromecast SSID (Example: Chromecast1234, Living Room TV, Bedroom TV, etc.) > Go to the Google Home app and try to set up again.
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