Modify Admin e-mail account

Modify Admin e-mail account

Aaccidently i have registered an email account (fabrizio.ciavatta@espertia.com) for admin user.

I want it to be contact@espertia.com

As well as i want to activate an account fabrizio.ciavatta@espertia.com that i have created but have no idea how activate it.

How to fix? Please help!