Playground on my property

[Andrew Karlin]

I bought a SFH in 2021. It's a 1acre lot that borders a school. I wish I could add a photo but on all the parcel maps and zillow, it shows my parcel as a rectangle as far back as my neighbors.

But when I purchased the place, the documents showed it as a rectangle with a notched out area for a small playground. The information/papers I got when purchasing is the only place it shows the boarder allowing the playground.

I’ve talked to some neighbors and they told me a teacher lived there long ago (was a foreclosure that was empty 3-4 years) allowed them to use the land for the playground.

What would the steps be towards figuring out if there was an addendum or on paper agreement giving them permission to build on the property. And if there wasn’t what are the steps you would take to resolve it. Thanks!