Need help folks. My father has his Apple ID linked to a now defunct email address. He couldn’t remember his Apple ID password, so he went onto the icloud on his PC which remembered his password for him. He changed the Apple ID email and password and all was well on the PC. He is now unable to remember the password for the old ID email and so is unable to sign out of the old ID on his phone and IPad . Is there anyway to get signed out to log in with the new Apple ID email on his phone and email?