Can Aunts claim their share of house even after an agreement

My Grandfather had a mud house in village near Narsinghpur MP. He had 5 girls (my aunts) and 1 son (my father). Grandfather got expired and in 2014 my grandmother wrote an agreement to put the house on my name by giving 10000/- RS to each of my aunts. Agreement (100 RS Stamp) also have signatures of all of my aunts and it's with me. I broke the mud house and making a sure house on the same place and it is in under construction. Currently my father is living in the house. Recently when my grandmother got expired, My aunts have changed their mind and they are asking for their share from that house. What should I do? Please advise.