Transfer of pagdi system property

Hi,

my grandpa had a shop in pagdi system building in Mumbai, when he was live at that time on the rent receipt there are thre names appeared 1) My Grandpa's name 2) my dad name 3) my uncle name.

but after the death of my grandpa my unclee has transferred this shop on his name without the notice of my dad.Now how my dad can claim in this shop? we dont have any rent receipt in our hand in which my ded name was there, all receipts are in my uncle's hand.