More than a simple 'Phishing' scam

My Virgin Media Account was set-up many years ago with an *.ntlworld.com email address. Several secondary accounts were linked to this and are still working perfectly.

Unfortunately, it seems that there have been several data breaches in the past. The main email address has been 'pwned', but none of the strong passwords that I use have been leaked.

A couple of days ago, people in my Address List started to receive scam emails. My email address had been 'Spoofed' - it was identical to the correct address.

I have informed as many of my contacts as possible not to respond, and to delete the emails from their systems.

The problem is actually more severe than this. The hacker is capturing all the messages sent to the *.ntlword address, and is generating more fake emails. Importantly, however, I no longer receive any of the messages.

I have reported the 'phishing' scams to Virgin Media Security who have given me some advice, but it does not really solve the problem.

I have changed my Virgin Media login address to one of the secondary accounts, so access to the original *.ntlworld.com account is no longer accessible. 

Virgin Media are keen to have a primary address that is not from Virgin. I have an account with another provider, but there were problems with authentication.

What I really want is for the original *.ntlworld.com email to be closed immediately, to stop the flow of information to the hacker. I still need Virgin Media account though!

How can this be done?