If you sign into Book Creator using an email address and password, we can update your email address for you.
Send us an email at email@example.com to prove that you own the email address you want to change.
We'll switch all of your libraries and books to a new email address, and then you just sign in with that new email address (use the same password you were using before).
You can also change your sign-in method from Google/Microsoft account to an email address if you wish. Again, just contact us if this is the case and we'll transfer your account. You'll have to set a new password the first time you sign in with your new email.