I've looked at that helpful answer and I can't do the first step every time I type in 192.168.0.1 on Chrome it says 'this site can't be reached' and on Internet Explorer it just redirects me to Google each time I hit enter.
You could try http://192.168.100.1/ to see if that works. That address is normally for when the hub is in modem mode but works when in router mode as well. If that doesn't work then try switching the hub off and on as sometimes (especially with the older hubs) the web interface stops responding and a reboot usually fixes it.
Disclaimer - I don't work for Virgin Media. I'm just another VM user trying to help out so my answers may be wrong If you do like my answer please mark it as helpful as it may help others My setup: Vivid 200 Optical fibre with Superhub 2 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.