Change the Wi-Fi network of Chromecast or Chromecast Audio
Make sure that your mobile device or tablet is connected to the same Wi-Fi as your Chromecast or Chromecast Audio.
Open the Google Home app .
Tap on your device Settings .
In the Device settings menu, scroll down to Wi-Fi, then tap Forget Forget Network.
Follow the setup steps to set up your device on a new network.

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