Memorable word

I've seen lots of posts about this, so I'm comforted knowing that many others have had this issue, but I'm not sure how to resolve mine.

I need a technician to visit my flat to set up my new Virgin Media account; one was scheduled for this morning, but I needed permission from my landlord before I was able to proceed with some work that needed to be done for set-up. Figuring out how to schedule a new appointment was its own hurdle. 

I have now telephoned Virgin three times; each time asks me for a memorable word in order to proceed with my request. Despite many other security measures in place for my account, I have not been able to get past that step. I have an active Virgin Media account that uses a passkey (a security method which was recommended by Virgin!), and I was never asked to set a memorable word. When I go into Account settings, there is no place, anywhere, to set up a memorable word. I have been through many posts on this forum trying to find a solution and have been unable to.

I'm so close to cancelling my account before it's even begun; I'm so frustrated. Seems like it was very easy to set up an account and everything else has been impossible.