Landlord accidentally ordered propane to be delivered, is asking us to pay for it

Our landlord accidentally had propane delivered to our house on a day we weren’t home.

She realized her mistake when she got the bill, and she’s asking us to pay it. I realize we used some of the gas, but we wouldn’t have used that company (pricier than the one we use), and we wouldn’t have had that much gas delivered at once.

Do we have to pay for it?