Hi@Daniel Ilbratt , thanks for reaching us.
I understand that you are asking to delete your old mail or add current mail to get right authenticating process.
The email address displayed on the Azure portal is associated with your Microsoft account, and not specific to Azure.
To delete or change your mail address contact your Global Administrator, ask them to add your new email address. The Azure Global administrator can delete or change email address for you.
For your reference: https://learn.microsoft.com/en-us/microsoft-365/admin/add-users/change-a-user-name-and-email-address?view=o365-worldwide#change-a-users-email-address
If in case, you are the only Global Administrator of the tenant. In that case you need to reach out to our support via phone (https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2) to create a support ticket and work with Data protection team to add new email.
Hope this helps. Do let us know if you any further queries.
Thanks,
Navya
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