@Ghost_1200 

Please confirm whether other Tapo devices can be controlled with Google Home normally.

Check whether you can control this Tapo P100 remotely with Tapo APP while using cellular data or other WiFi? 

If this device can only be controlled in the local WiFi network, here are some tips that might help with this issue:

1. Reboot the device manually: unplug and replug Tapo P100

2. Remove Tapo service in Google home APP and reconnect. 

(1) How to remove Tapo service <Google Home: Remove third-party account access>

a. Go to the Security section of your Google Account.
b. Under “Third-party apps with account access,” select Manage third-party access.
c. Select the app or service you want to remove.
d. Select Remove Access.

(2) How to connect my Tapo device (smart plug, smart camera, smart lighting) to Google Home

What's the hardware and firmware version of the problem P100? Please share device's Mac address (APP> Device Settings >Device Info) with me via PM, we can help to check if there is any abnormality. 

  @Ghost_1200 

Thank you for the update, glad to know the device is working now!

This thread will be locked as this case is closed. If any user encounters similar issue, please start a new thread together with your device information (model, hardware, firmware version), problem details, and the troubleshooting steps you have tried.