If there are no local area outages then the fastest way to get it fixed is usually to call VM and report the fault or you can wait for the forum team to get to this thread in a few days time.
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 my answer solves your problem 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.
It has been fine since the engineer called today. Everyone in the street is experiencing the same issues after a virgin sub contractor moved the junction box and didn't bother making sure any of the connections were fitted properly when reconnecting. Obviously not quality assessed before being put on the virgin suppliers register.
Direct virgin engineers are a credit to virgin though, couldn't fault him, and it's the second time the same bloke has been out and fixed an issue.