If you are using the au Email Portability service, you can reconfigure the email app from My Page.
Please see below for detailed instructions.
Tap on "Email app settings" [メールアプリの設定].
If you are using an iPhone, proceed to Step ③. If you are using Android or Gmail, please proceed to Step ④.
For iPhone/iPad
Tap the "iPhone Mail App" [iPhone 標準メールアプリ].
For Android
Tap the "Android au Email App" [Android auメールアプリ].
For Gmail
Tap on "Check the ID and password required for email settings" [メール設定に必要なID・パスワードを確認する].
For example: If you cancelled on April 1st, 2021
au ID before cancellation: 080XXXXXXXX
au ID after cancellation: 080XXXXXXXX_20210401
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