Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
2 strikes.
There is an Office 365 Home yearly / monthly subscription. 5 user (now 6).
There is an Office 2019 Home and Student one-time payment / "lifetime" license. 1 user
There is NO Office 365 Lifetime ... strike one.
Both of those licenses use your own email account, a hotmail.com or outlooklive.com account NOT an email account supplied by the vendor ... strike 2.
If it was a school account, was it an *.EDU account?
I don't know what you had, but without the proper bundle name there is not much more we can do.
Have you tried contacting the vendor?