Improper division of land between joint owners what can be done

Hi, My mother (A) is co-owner of a farming land with an area of 0.4 Hectare in Bijnore, Uttar Pradesh. There were total 5 owners (A, B, C, D, E) of this land. 3 owners (B, C, D) decided to sell their part (0.2 Hectare) to my mother. My mother paid them (B, C, D) for 0.2 Hectare. But due to some error in the area, my mother only got 0.02 Hectare land from these 3 people. Now, person E is claiming that He is the owner of the remaining land (02-0.02 = 0.18). Moreover, Patwari has generated a Sanad for the same after taking some bribe. I have 3 questions: 1. Is my mother still owns that remaining land despite the sanad patwari has generated to person E? 1. If yes, how can we can get the remaining land? 2. Can we file a case against patwari as he willingly generated a false government document?