My grandfather's farm land is taken away by my uncles after my father's death

My grandfather had some farm lands, my father were 5 brothers. Eldest brother just took big chunk of land only because while he was young (below 12 years), my grand father bought farm lands on his name. After his wedding he did not give anything out of his named property and got aside. Now, 4 brothers are remaining (including my father). My father expired this year and my 3 uncles never gave our share of farm land. Land is in Punjab, and for every small things, a lot of bribe is asked. We stay in Haryana and Maharashtra, and we got to know my uncle (out of 3) is trying to sell the land. They had a concept of girdavari which per them has statement that my father has no more share in his land. However, there is intekal where my father's name is mentioned. I want that we being part of my father's nuclear family should be able to get what he inherit from our grand father's property. How can we stop them to sell the property without giving our share. And, what could be the lumpsum expense to get this issue sorted.