Lost access to NTLWorld account
My father has had an ntlworld account for years and has been a continuous Virgin Media subscriber for quite a long time. He uses a secondary account for his email in the form firstname.lastname@ntlworld.com.
Today he told me he wasn't getting any emails. I tried logging in for him but the password was rejected so we tried a password reset but that page said his email address was not valid. I logged in with his main account and tried to access mail but got a "Your Virgin Media Mail account is currently unavailable" page. I followed the instructions as far as "Tap Manage next to Manage your Virgin Media Mail app password under Virgin Media Mail", but that option does not exist under his account settings. There are no mail settings at all.
I also checked the "manage other accounts" and saw that a strange email address was there, so my assumption is he somehow got hacked and someone altered his email address and password, so messages to his ntlworld address no longer arrive. I deleted the false account and tried to recreate his original, but this sends an email to the account for verification, and we can't access the account until it is verified.
I've also tried logging in through the Android app but that also has no mail settings.
Can anyone at Virgin help him get his address back?