Konami Account Hacked, Email Changed And Access Fully Lost

Today my Konami online account was hacked and the person who accessed it changed the email address linked to my account. As a result, I completely lost access to my account and cannot log in anymore. Right after noticing the issue, I contacted Konami customer support. However, I was told that I do not have an account, even though I have been using this account and know my old email address and username. I can provide my old email and username as proof that the account belongs to me, yet I still have not received any help in recovering it. I request that my hacked account be recovered as soon as possible and that access be restored to me using my old email and username as verification, or through any other security verification method Konami finds appropriate. I expect my account information and progress to be reinstated and the unauthorized changes made by the hacker to be reversed.