
Do not log in via Settings; log in via App Store whenever possible
If you log in via Settings, Find My iPhone will be enabled by default
In this case, if the account is banned or the password is forgotten, you will not be able to log out of Settings.
After flashing the device or restoring factory settings, you will be forced to enter the Apple ID and password, otherwise you cannot access the system interface.
This is how a phone becomes bricked.

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