You can change the e-mail address for login with the following steps.
1. Access the Account page.
*If prompted, enter e-mail address password to log in or re-enter your password to submit.
2. Choose your profile.
3. Select [Edit] next to Account Information.
4. You can edit the e-mail address.
5. Select [Finish].
*If you don't see your account information, please switch to the owner profile and reaccess the Account page.
You can also change the e-mail address for receiving notification about Service and Updates.
Please refer to this help article: How do I enable or disable email notification about Service and Updates?