Cancellation of Settlement Deed

Dear sir, My father owned a self acquired property. we are 3 sons to our father. Our elder brother influenced and requested by his affection and made settlement deed in 2014. At the time of deed registration he also gave promise to my father and mother that he will take care the property and will do justice to other 2 brothers and my mother. Unfortunately In 2015 December my father died . We were felt he will make justice . But In 2018 he sold the property to others in with under value consideration and kept in silence without our knowledge. We did not know the transaction due since he lives in the same house up to 2022. In 2022 the other party sold the same property to another party without our knowledge and also my brother . The concern property gave balance value worth cheques and vacated my brother . After vacated the house by our brother then we came to know the present situation. Now shall we file suit against the settlement deed for cancellation by two brothers or my mother . Since there is justice to us in this transaction.