Why is my Microsoft account connected to a Playstation account?

I want to connect my Microsoft account to my Playstation account for Minecraft to play on realms, but whenever I try to, it says: "Oops! Looks like the Microsoft Account you are trying to use is already connected to another account on 'Playstation Network'. Please sign in with a Microsoft Account that is not already linked to an account on 'Playstation Network'."

My Microsoft account should not be linked to any Playstation Network account, seeing that it isn't connected to my own. I've checked every other account on the Playstation console just to be sure, and found none of them were connected to my Microsoft account. I do not want to have to use a separate Microsoft account, if I can even do that...

Any help would be appreciated.

:)