Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello, thank you for reaching out to Microsoft Q&A.
It’s possible you used a different Microsoft account for the purchase, and the license is registered to that account?
Please open a new InPrivate/Incognito browser window and sign in with each Microsoft account you remember on this page:
https://account.microsoft.com/services
Check which account the subscription is linked to. Once you find it, you can download and install Microsoft 365 on your Windows device again using that same account.
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If you are having difficulty finding the subscription, find your username using the alternate recovery information.
Forgotten your Microsoft account username
You can see the partial email address linked to your recovery information. Try to recall that account and check if the license is associated with it.
Let me know if you still need more help.