Google constantly updates its Google Home and smarthome range. With a recent update, you will need to unlink and link some of your smarthome services in order to continue using them and take advantage of new features. Here's how to do that.
If you have a Google Home account and you use smarthome services, you may have received an email like this . In this document, Google indicates that a future update will bring new smarthome features. Although we do not know exactly what the new features are, Google clearly indicates that you will need to connect your smarthome services to continue using them and get the new features. This is boring, but apparently necessary.
To update your smarthome services, open the Google Home app and press the menu button at the top left, and then tap Home Control.
On this page you will see a list of your smarthome services. Next to some, you'll see the word Upgrade! in parentheses. If you see one, press the plus icon in the lower right corner.
At the top of the list you will see a list of your connected services. Press the Upgrade! next to it.
A dialog box will appear with only one option for "Unlink account". Tap on it, and then confirm that you want to continue by pressing Unlink in the next box that appears.
Then again on the home screen, press the bigger icon again down
This time, you will have to scroll through the list of services and find the one you want to add. Touch it.
You will need to reauthenticate your account by entering your email address and password and then allowing your account to sign in again to Google.
It is a bit annoying that Google has not explained exactly why this is necessary, but if you want to continue using your smarthome gadgets with Google Home, you will have to do it once.