Joint family property registered in Uncle name,rejecting to give share

My Father & Uncle were working together in same field.my father purchased a plot and registered in his name and constructed 2portion of house,where My father(elder),Uncle & grandpa were living in 1 portion in joint family.again after 2yrs my father purchased some land got agreement registered in his name & made sale deed in my uncle's name.when my father and uncle got separated,they came to mutual understandings that both ll have equal share in both the properties hence my uncle family started living in other portion of house which is in my fathers name(but they didnt made any papers)after some years both my uncle and my father died..my uncle family lived in that house for 15 years now they are vacating,The valuation of my uncle's land is 5times more than that of the house because of that my uncle's wife and his sons rejecting us share in land by saying we dont want ur house we will keep our land only,the grandpa's property is still in my father and uncle's joint name.please advise