Changing the main user profile name

Our company Mobedig has an account and there are 3 admins, including me. The account however has been created by our ex-CTO who no longer works for us. We would like to delete his email account but would need to change the main users at all cloud services our company uses.

How do we do the change here at Auth0?

If the account already has other administrators with the All applications permission then you should only need to login into Dashboard with one of the other administrator users and remove the administrator entry associated with the user that has left your company.