If a last will is valid, why tahsildar refuse to give a patta

I'm go to tell you a small story. my grandpa mother has 6 daughters and 1 son(My Grandpa).... His mother write a first will to his daughters.... after they got the will,They threw their mother out of house like a waste... then my grandpa gives a hand.... then his mother written another will for My Grandpa.... after that she dies and also we only one has a death certificate of his mother.... after 10 years, we go and ask a patta to register office.... also his sisters also ask a patta... hence encumbrance comes.... after that my grandpa sells it to his wife(My Grandma) brother who is very rich to get a patta easily.... but grandma's brother didn't give any money.... so he sells land to my grandma (wife of my grandpa). after that right now she is owner for that..... and also my grandpa dies before 5 months on this post. Today, Village Administrator Officer told my daddy to ask grandpa sisters to withdraw the encumbrance.. my doubt, if last will is valid, why they need a first will help to give a patta. Please help ya. also thanks for reading. leave your idea in comment please... Have a great life...