Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Dear Philipa,
Looking at the error, this is coming from Sparx Learning, which is a third-party platform your school uses, rather than from Microsoft directly. The message means your email address has not been found in Sparx's own system, so unfortunately this is not something that can be resolved from the Microsoft side.
The quickest route would be to speak with your teacher or your school's IT support, as they can check whether your account has been set up correctly in Sparx and correct it if needed. If you don't know who your IT administrator is, please refer to this article: How do I find my Microsoft 365 admin? - Microsoft Support
I hope you get this sorted quickly. Please let me know if you need anything else.
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