Civil Law

A person took a room at the market from Municipal. and after that i took that room as rent from the owner. And after that i also gave the same room to a person. i make an agreement for 11month, but did not renew after complete 11month.. now complete 4years without renew.. i take mothly rent and a small amount i took itself and then i give some part to the actuall owner.. in this way its going good.. but now arise a problem that is, the person to whome i give the room he did not pay Electrisity bill for many years.. now is about 40,000.. i say to pay bill... he always said ok i give..but not pay.. i feel he trying to go anather room without pay the bill... What am i do? if he not pay then the actuall owner direct me to pay.. now what is the remedy?