• Sale agreement

My father made a sale agreement with a broker to sale 2 plots of land for sum of 20 lacs to be executed within 4 months. my father received 10 lacs from broker made a  receipt of 10 lacs on agreement paper and executed sale deed of 1 plot to a third person as requested by the broker.
                                    After 5 months my father expired. Now broker (dishonestly) claims that he has paid 10 lacs and got nothing(because agreement was made in his name). he says he is ready to pay the remaining 10 lacs but he wants 2 plots. but he has already taken 1 plot in the name of person requested by him.