You can complete the change procedure at the "au ID Member Information Site" [au ID会員情報サイト].
On the smartphone, tap on [MENU] icon at the top right corner of the screen.
Tap on "au ID Member Information" [au ID会員情報].
Tap on "Change" [変更] on the right side of the "Password" [パスワード] section.
Enter your new password and tap on "Set" [設定].
Example: A password that is at least 8 characters or more, do not include your birthdate, name, or phone number, and is not used on other sites.
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