Help required!

Property division is going on in my maternal grandmother house . My mother has 3 brothers and 2 sisters. Most of the property ( around 120 bigha worth around 300 crores) is located in center of a district in Bihar . I recently got to know that my mama (maternal uncle) has made my mother sign noc 2 years ago. Mother's sisters are yet to sign noc. Is there anything I can do now to prevent this fraud from continuing?