The customer service is awful. The phone line will often disconnect between 50-75 mins according to posts on social media and these forums. Even if you make it past that point you're unlikely to get through unless you hold for between 90-120 mins which is obviously totally unfeasible for most. On these forums the wait time for a response is about 5-7 days. Which doesn't leave with you many options...you're in the same basket as hundreds of others with a fault that can't be fixed or even reported.
If you're dissatisfied you have the option to file a complaint. They have 8 weeks to respond to your complaint and following that you can appeal or take it further to CISAS or another independent adjudicator. I'd recommend filing a complaint partly because it's seemingly the only way to put on record what's going on and also because these complaints (and whether they're successfully resolved) do form part of OFCOM's annual report which affects what Virgin can say about their service.
It's a tough time at the moment and the horrendous customer service is making life a little bit harder for a huge number of people.