Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hi Andrew,
Welcome to the Microsoft Q&A forum.
Based on your description, you would like to cancel a subscription for a business account, but you currently do not remember the sign-in information for that account.
Typically, Microsoft business accounts may use a domain in the format @xxx.onmicrosoft.com.
Please try searching your mailbox to see if you can find any emails containing information about this domain or account.
In addition, I have sent you a private message. Please check it when you have a chance.
I look forward to hearing from you.
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