My Uncle Filed A Specific Performance Suit To Direct Her To Register That Land T

Sir,my grand father has 10 acers agricultural land.He announced 1.00 Acres Agriculture land as Pasupukumkama at the time of my mothers marriage. my grand father and her brother executed a Registered Gift Deed 1984 to my mother. My mother filed a partition suit in 2016. so my uncle filed a specific performance suit in 2017 that she sold her land in 1984 and made an sale agreement and asking the court to direct her to register that land to him. He said he fully paid the sale amount to my mother. He cheated revenue authorities and got his name in land records.In register office that land is in my mothers name because of registered gift deed but in revenue records my uncle name is coming. When the suit is still pending in the Court, my uncle sold my mothers land on 30-10-2019.I heard that person who seeks relief must come with clean hands.so please advice me on what ground we can fight this case.