You will have to decide if you want to delete the address or attempt a Move & Transfer. If allowed and possible, this would replace your existing emails/mailboxes attached to the billing account, with the old email addresses and mailboxes. So not a decision to take lightly. And of course, the Forum Team have to apply VM's data protection rules and technical limitations to the request either way.
Let us know if you need assistance or advice, the Community members are here to help.
Thanks for taking the time to post on the forum in regards to your email password issues, we don't have many rules here but we would ask you not to spam post the thread. It doesn't get the query answered any quicker and can cause issues further down the line.
Can you confirm the following please:
Do you still currently have active Virgin Media services?
What happens when you try to reset it via the forgotten password link on the sign in page?