• father's property to his sons

Im kiran, from nizamabad
When my anger  brother is minor (3 years), my father as registered agricultural land of 1 .5 accar to my brothers name. So, my brother is warning us the property is mine. But,  the patta book was not given by registered name (brothers name). It has given to my fathers name. The registration has done in 1976.
                          so, please tell the solution to solve our problem.