Help accessing account

Really hoping someone can help as now just stuck!! My husband is registered with an account for both our house and his parents and has been for sometime. It has now come to an end and the bills has now increased. He recently lost his email address that was registered to the account and unable to get it back/any emails to that address: he has also changed his phone number but did not change them with virgin. He doesn’t get postal bills so no way of finding out his account number and upon calling virgin media he is unable to pass security checks to speak to someone to either cancel/renew his contract and are now stuck in a continuous cycle of being charged a lot! When we did call last time they would accept an outstanding balance from him (which he paid) so they can see the details but won’t speak with him regarding anything further as he doesn’t pass security checks. Surely there must be some other way around this as people do lose emails/phones etc! Please can anyone help/advise. Thanks in advance