Area Reference Code

I’m trying to link my O2 and Virgin Media accounts and I’m unable to do so because it requires an Area Reference Code. 
I have never been issued with this code as I signed up two weeks ago over the phone and have not received any correspondence from Virgin by email or regular mail. 
Can you supply me with an Area Reference Code for PA4 0EG as I really don’t want to spend another hour on hold to get an unsatisfactory response to my enquiry. 
TIA