Odd. You should have received a welcome pack, which would have had that info contained within. The e-contract you signed would contain that info and the welcome emails you get shortly after signing up contain that information also. For whatever reason, you haven't received all the information you should have.
In some cases staff will clear DPA with you if you provide other account related details.
So for example you could call 150 from a VM phone / 0345 454 1111 from any phone -> calling in about a broadband etc matter -> choose the enter your details steps -> it will prompt you for details twice, key nothing in. After said two prompts it should give you two options, if one of those is a new customer option (option 2), go with that, then -> option 4. If there is no new customer option, just go with the existing customer option then from the menu choose option 4 -> option 5. That'll get you through to helpful UK based staff. They're available M-F 8AM to 8PM, Sa 8AM to 6PM.
Or try asking via the web chat: Account and billing -> managing your account online -> Chat Online. If it says all agents are busy, reload the page every 3 minutes and check again. Do so from a desktop/laptop between 8AM to 8PM M-F, 9AM to 5PM Sa.
______ Any opinions expressed by myself are entirely my own and do not represent Virgin Media in any way.