My father gifted me our ancestral home in India. My uncle, who owned the property next door, sold it to a neighbour 25 years ago. We’ve always shared a common wall peacefully. Now, after I started renovating my house, the new owner claims his property is 2 feet smaller than what’s on paper. He refused to show me his documents and threatened legal action. I had to build my wall 3/4 foot away from the shared boundary. We even made a formal agreement on stamp paper. But now he’s denying the agreement and says I can’t build a wall at all. What legal options do I have to protect my property rights?