My landlord has 2 gas meters and 2 gas heaters, but only one is connected.

I had a problem in my basement and found out that the landlord has 2 gas heaters, but I live in a apartment with 2 floors. I have the first floor apartment and someone rents the second floor. We pay seperate gas bills, but I saw one pipe coming out of the heater, but then it splits into 2. And my heat doesn't always shut itself off. The other heater is not on. Is this legal? How can we pay seperate bills if there is only one heater working? Who do I call about this? - Is this your question? Add additional information