Question regarding land encroachment

Hello Sir, I am a NRI residing in the USA. We have a plot in Hyderabad and my father gifted a portion of the plot to my sister on her marriage. The original plot was registered on my father's name and my father expired in 2009. My brother-in-law encroached to our land and constructed 5 floors building. I engaged a licensed surveyor to survey the entire plot, my sister building and remaining vacant plot. The survey report clearly indicates that my sister's building encroached our land. Below are the details of the areas: 1. Total area of the plot = 520 sq. yds (per registration documents) 2. Portion of land gifted to my sister = 250 sq. yds (per gift deed registration document) 3. Building area in my sister plot = 290 sq. yds (per licensed surveyor report) 4. Remaining area = 230 sq. yds (per licensed surveyor report) I am at a loss of 40 sq. yds and when I tried to explain her that they have encroached my plot, my sister is saying that she has constructed per dimensions in the gift registration document. I tried to explain that her gift deed is entitled to 250 sq. yds but she is not ready to talk over this issue. Kindly suggest the best possible approaches to deal with this issue.