Hello,
Once after deactivating your email, you can’t be able to sign in to Mendix account using deactivated email. Using your new official email you have to create a new Mendix account and set your profile to Public & then submit a merge request (By entering old Mendix email) which will merge your mendix old profile points etc to your new mendix active account.
Refer to this account regarding Mendix profile merge
https://docs.mendix.com/developerportal/community-tools/mendix-profile/#1011-merging-profiles
Hope it helps!