You can't edit a user profile's email address directly. To switch, invite the new address as a new user, then sign in from there.
Invite the new email. Signed in with your current account, invite the new address as a user and assign it the role you need (for example, Super Admin).
Sign out of your current session.
Accept the invitation. Open the invitation email sent to the new address and follow the link to finish setting up the profile.
Remove the old profile (optional). Once you're signed in on the new email, deactivate or delete the old user to keep your team list tidy.