We live in a duplex. Our landlord receives one gas bill and one electric bill for the duplex. When we first moved in she payed both bills which was part of our lease agreement. Recently she started making us pay half the bill and the family who lives in the other half of the duplex the other half of the bill. Can she do that even though we have no control how much gas and electricity the neighbors use. We are no longer on a lease and just on a month to month basis.