I would like to know how to remove one of my email addresses from my ZohoMail account?

I currently have two email addresses in my account.
The 1st email address created is seen as to administrator. Then I created a 2nd email address. 

I would like to remove or make inactive the 1st email address I created but it seems difficult as the email address is linked to the administrator account.

Any advices?

Cheers

A.