praveen from bangalore

Hi all I just need one clarification . My dad bought a sight 10+years ago in bangalore at Hoodi circle and after so many years we have decided to construct. All of a sudden some people asked us to stop the work as our site was road hitting and they want it for road for back side empty lands and they said like they will purchase our land and asked for one copy of our site documents. We have paid taxes upto the date but those people are saying like the survey number mentioned in the document doesnt belong to the site which we have planned to construct whereas that survey number points to the left side of our current site because of which they regret to buy our land and even we have proper B khata. How do i able to confirm that survey which mentioned in our land document and where exactly it belongs . When we asked for Rectification deed from my land lord he is regreting for it. I just want to know which is my site and how do i make confirm about it so that there should be any problem even if i construct home on it. Please do help on this.