move a custom domain email address to a mailbox of a family member
I would like to remove one of my email aliases (john@mydomain.com) from my mailbox because John now has his own family account. I've removed the alias from my account, but when I try to add the address to John's account, it doesn't work, I get the error message "This email is already in use with another Apple ID." What can I do to get this done?