Is an agreement of one lakh valid on 50₹ bond paper

Sir,I am selling a land to a person(taken advance) but he is trying to sell that land to other person whom I don't wish to sell so I want to cancel that land agreement but he is not agreeing .pls tell me some tips to defend my land. I got some mistakes in bond paper: 1. 50₹ bond paper for 1lakh rupees advance payment by cash 2. The bond paper purchased person name and person to whom I am selling the land are different Please tell me are these points valid to cancel the agreement.