Property Matter

I don't understand what to do, about 25-30 years ago my father purchased a shop by giving some amount as paghdi as we are still tenants. But the problem is that we are here in shop from 25-30 years but the reciept is not in the name of him, it is in the name of relative and only proof of our tenacy is cheque payments of all the time period and landlord is asking now where is the person whose name is written in slip. What to do next i can't understand suggest me and he is also not taking rent.