Got email from SE Support:
Dear Customer,
Regarding your request for account support. Please find your answer below.
If you accidentally registered the code for the Beta Test to the wrong service account, we will be able to offer a one-time assistance after you verify your account.
Please take the following steps to contact the SQUARE ENIX Support Center and receive assistance.
(1) Click ?Additional Assistance? at the bottom of this article.
(2) Log in to the Square Enix account that you are experiencing the issue with.
(3) Enter ?Beta Code Registration Issue? in the ?Contact Details? field.
(4) Click ?Next,? ?Next,? and then ?Proceed to Email Support.?
(5) Enter your contact details. Please be sure to include your registration code within the ?Detailed Condition? field. Once you have entered all the necessary information, click ?Next.?
(6) Verify the contact details and then click ?Submit.?
Thank you for contacting the SQUARE ENIX Support Center.
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