Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello, CS.
If you don't remember which account you subscribed to, then check in the "Subscriptions" settings of each of your accounts.: https://account.microsoft.com/services
And also in the "Order history" section: https://account.microsoft.com/billing/orders
In which account the 365 subscription will be displayed, then the account login is the same.