Thanks a lot for your message on the GOOSE VPN community.
Unfortunately it is not possible to setup GOOSE VPN on a Ziggo Connectbox.
We’ve tried this multiple times but it looks like it is not possible to use this combination.
In case you want to install GOOS VPN on a router to protect your whole network at once we recommend switching to another router to put after the Ziggo Connectbox. Another option is installing GOOSE VPN on your device separately, this will also protect them outside of your home network.