If you update iOS or change your Apple ID (email address), you will need to update the settings on the device (Mac, iPhone/iPad, etc.) linked to your Apple ID. Some account services will not be available until you update.
Update your Apple ID settings
Launch “Settings” from the home screen
Update your Apple ID settings
Enter your Apple ID password
Enter iPhone passcode
Apple ID settings updated
Apple ID is locked
Home Screen
iPhone settings
Update your Apple ID settings
Enter Apple ID password
unlock account
Enter passcode
password reset
New Apple ID password
Sign out from other devices
Account unlocked
Error connecting to Apple ID server
Mac - Update your Apple ID settings
How to use and set up an Apple ID
iPhone usage and settings
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