two MS accounts

"I appear to have two subscriptions for MS365 when I only need one , how did this happen?"

I can't think of why someone would hack in to your Microsoft account and purchase a second subscription to Microsoft 365 for you. Is it possible that you made some mistake along the way? (I myself have done much worse!) You can cancel the unneeded subscription and possibly receive a refund, depending on the circumstances.

First, sign in with the email account(s) you might have used and check your subscriptions here:

https://account.microsoft.com/services (Microsoft Services & Subscriptions)

See if Microsoft 365 appears there.

If you find subscriptions on both accounts, keep the one you use regularly and cancel the other subscription on the same page (this only stops future renewals and will not affect the data you have already used).