The exact causes for Google cloud printer offline are unknown at this time. If the Google Cloud printer is not operating properly, an error message will appear on the screen of your device. Apart from just uninstalling and reinstalling the appropriate printer driver or reconnecting your Google Account to the Cloud Printer, there are a few options you may try. Other causes include:
The printer and your device are not connected properly.
Slow Internet connection or a printer power supply that has been disconnected.
Your device's configuration/setting is incorrect.