@Go Maruyama Thanks for posting in our Q&A. For this issue, it is not realted to windows 365. It is related to Office 365 E5 license itself.
Based on your post, it seems that this issue occurs to verify your account identity to access Office 365 E5 subscription. With the limitation resources, it is suggested to call Global Customer Service phone numbers to get accurate help.
https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
Thanks for understanding and hope everything goes well with you.
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