Claim by Kolkata Port Trust of 30 lacs penalty unpaid rent ofplot

Father took a plot of 200sqmt at Kolkata Port Trust, kidderpore siding in 1972 for business of trading coal brought by railway wagons by access to available railway track on terms of 1 year security deposit in addition to monthly payment of rent . Later without ref to him the Port (then called CPT ), uprooted the railway tracks in 1979. This disrupted biz of Bringing coal from Dhanbad by Rly wagons. Biz failed. I was small. He died of shock.No biz, No rent. Now after 35 yrs CPT last week served a hand delivery show cause notice of rent arrears plus interest, penalty totalling 30lacs, n to come meet related highest officer in Head Office. They ask why I did not inform about father's death to them. I said not aware it was so required. I am a man unemployed n uneducated living with grown up daughters, n a pauper, cannot dream to pay up that astronomical demand. I have never used that plot, & wish to surrender.Then they ask why I did not formally relinquish the ownership.i said I know not the procedure. If they cut off Rly track access, relocation for biz should have been provided. Then is their demand maintainable for not doing so. ? & are they not vulnerable to my counter claim of destroying my father's biz, & pushing a successor generation into economic depravity. Cannot say whether plot was leased or on licence. CPT has given me a week's time to reply.what action should I take.They have my native place address, but there is no property there in father's name .All sold off survival by my mom who too is long dead.But will they go that far to my native place & what can they get there? I need a good advocate in Kolkata next week for consultation, and if CPT institutes recovery proceeding, I would wish to even retain the advocate to handle it, & other things. Kindly some intelligent lawyer respond. Thank you.