Additional features, settings, or issues not covered by specific Microsoft Teams categories
Thank you for posting your question in the Microsoft Q&A forum. I understand how concerning it can be to be unable to sign in while still being billed for a subscription.
When a Microsoft 365 tenant is created, Microsoft automatically assigns a default tenant domain in the format tenantname.onmicrosoft.com. This onmicrosoft.com domain is used as the foundational sign‑in identity for the tenant, particularly for administrative access and subscription management.
In many cases, the email address that receives invoices or billing notifications is not the same account used to sign in to the Microsoft 365 admin center. Billing contact emails can be updated or used only for notifications, but they do not automatically function as sign‑in identities. This may explain why signing in with the email address that receives invoices results in a message indicating that the account does not exist.
Because of this, it may be helpful to try signing in to the Microsoft 365 admin center using the original onmicrosoft.com account that was created at the time of purchase. This account typically has administrative permissions and is required to manage subscriptions, including cancellation.
Additionally, I have initiated a private message for your convenience and left a note there. At your earliest availability, please review that message so I can assist you more affectively.
To access your private messages, sign in to the Q&A forum using the account you used to post your question. Then, navigate to the Private Messages section to view and respond.
Thank you for your attention to this matter. I look forward to your response.
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