Ring 1571, it should give you options to configure your voice mail as you need.
If voice mail isn't enabled for your line, you can call in and ask for it to be enabled: ring 150 from your landline -> confirm your details -> go into the menu system -> then either faults (option 2) and report a phone fault. Ask them to enable it. Or option 4 -> option 1. Ask them to enable it.
There's also the web chat, which should be accessed from a desktop or laptop, between 8AM to 8PM M-Sa: Phone -> Service fault or area outage -> Chat online. Ask them to enable voice mail.
Note: Disabling or enabling a feature, such as voice mail can take up to 24 hours to complete.
- - - - - - Any opinions expressed by myself are entirely my own and do not represent Virgin Media in any way.