You can cancel the service from the My Page of the au Email Portability.
Access the page of au Email Portability from the smartphone you are using the service on.
Scroll the screen from bottom to top.
Tap "Click here for application/My Page (au ID login)" [お申込み・マイページはこちら (au IDログイン)].
Enter the au ID of the email address you want to cancel and tap "Next" [次へ].
Enter your password and tap on "Login" [ログイン].
Tap on "Cancel service" [サービスの解約] on My Page.
Tap on "Proceed to confirmation screen" [確認画面に進む].
Confirm the important notes below and tap "Agree to the notes and cancel" [注意事項に同意して解約する].
When "Cancellation completed" [解約完了] is displayed, the cancellation of the "au Email Portability" service is completed.
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