Issue with Google Assistant integration: devices:reportStateAndNotification failed: 404


When I add a new device using Home Assistant or when a new Hue device is added to the Hub then is added to Home Assistant, I have the following error multiple times:
devices:reportStateAndNotification failed: 404

I Read the Troubleshooting section of the Google Assistant Integration documentation and found the 404 error is when Homegraph API is not enabled for the project.
I was sure to have enabled it before but I began again and paid particulary attention when checking the project ID where I enabled Homegraph but the error still occurs.

Has someone succeeded in solving this issue?
Because I have to manually sync my device when it should be done automatically and I am sure to have followed the documented instructions.

Except this issue everything works right when using my Home Assistant devices with Google Assistant.
I use Home Assistant OS in a Qemu VM managed with Libvirt on Debian Buster.