You can delete your account in-game by following the steps below:

・Account Reset
If you wish to start over from scratch, please perform the following steps in-game:
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1.) Open [Options].
2.) Go to [System], then select [Reset Account].
3.) Read the precautions carefully, and if you don't find any issues, check "Confirm" in the lower right corner.
4.) A confirmation prompt should appear; check all the boxes if you don't find any issues.
5.) A final confirmation prompt will appear next; check all the boxes if you don't find any issues.
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・Account Deletion
If you wish to delete your account, please follow the steps below:
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1.) Open [Options].
2.) Go to [System], then select [Delete Account].
3.) Follow the on-screen instructions to submit your account deletion request.
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If you can't delete your account on your own, please feel free to submit a request using the form below:

■Precautions Regarding Account Reset and Deletion■
We will perform the following actions only if you send us a request:
1.) Account Reset
2.) Account Deletion
*Once your account is reset or deleted, you can no longer log in to it.
*Any data from deleted or reset accounts cannot be restored.
*Any remaining data in the account will be deleted, including items, currencies, and subscriptions. They cannot be transferred into a different account or refunded.
*Account deletion will usually take time to process.
*Please keep in mind that account reset/deletion requests generally cannot be canceled once submitted.

The following information will also be deleted when your account is deleted. Please keep in mind that they cannot be recovered even if you contact us:
1.) Any data linked to your user ID (play data, owned items, etc.).
2.) Any data shared with third parties (entities other than you and SEGA).

Please read the "Precautions Regarding Account Reset and Deletion" above carefully and contact us using the form below only if you agree with the terms explained to you.
*You must also consent to our privacy policy, so please do not use the form unless you consent.

■SEGA Corporation Privacy Policy
https://www.sega.co.jp/en/privacypolicy/index.html