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It's difficult to tell from the plan, but there aren't any easements/rights shown. So the path is on one person's land or the other's.
Fence along the boundary. If that doesn't solve it - because the access path is on the neighbour's land - then gubhi doesn't have much of a leg to stand on anyway.
Anecdotally, our shed is on our upstairs neighbour's land, technically, because it's under the outdoor steps from their roof terrace to their part of the shared garden. That strip of land is shown as blue on the deed plans.
I would put a fence up, along the boundary. I'm not even kidding.