I need to change the admin email to another email on my account. 

I am the owner and I am all seats on the account, however the admin email is on a domain that I have no control on, and I don't have access to that email anymore.

Linking email don't work as all emails I have are already registered to a box account.

Changing admin to another user doesn't work, as the other users are on a different domain.

I still can access all my files on the admin account, I have 2FA active and I have all my ID to prove who I am, including the credit card paying for the account, account which I always been the only owner.

I have notifications sent to another of my email that I have control on.

I deleted the managed domain in case that was the issue.

I still need to change the admin email address, as that email is now compromised and I am afraid a password change by someone now accessing the emails could let that person access all my precious files.

I did all this back already a few months ago, but the ticket was sent to the email I don't have control despite my comments, and my issue is still existing.