Delete the Google Home app from your phone or tablet.
Factory reset your device
Follow the reset instructions of your device and afterwards follow the provided steps below.
Reinstall the Google Home app and perform the setup preferably when your phone/tablet is connected to the faster 5 GHz WiFi home network.
If you have a standard provider router with a 2.4 GHz and 5 GHz home WiFi network, we recommend that you separate these two bands by giving the 2.4 GHz and 5 GHz networks each a separate SSID (network name) and password. To do this, you must log into the modem. If you are not sure how to do this, we recommend you contact your Internet provider, who will be able to assist you with this over the phone.
In the network section there's an article witch explains how this can be done manually. Afterwards, be sure to connect the phone or tablet to the faster 5 GHz home WiFi network before you run the setup again. If you have made changes to your network settings, make sure that all your devices are registered on the ‘new’ network and make sure to forget any other networks with which your phone/tablet was configured to connect automatically.
Also please check out the article about preventing interference.
NOTE: If you are unable to easily maintain the wireless connection, this set can also be connected directly to the network with an Ethernet cable.