Father purchased a house in my name, wanted to convert it in freehold

My father puchased a house from hudco under leased hire scheme.He made a registered will in my favour bequeathing the house in my name.During his lifetime house could not be converted to freehold as state govt put a stop due to case filed in court of law.Now after his death stop on freehold has been lifted.I wanted to convert the house into freehold in my nameby enforcing the will.The state govt authorities are saying that will is null and void as a person cannot leave a leased property in his son's name as he has not taken permission from state govt authority(ADM) in this case.Nowhere in the leased deed is it mentioned that owner of leased property cannot make a will Moreover how was the will registered in court of law.My father is dead and gone .How do I proceed now.Please help me.