Gas Budget Billing- Huge lump sum owed when we moved

Gas Budget Billing- Huge lump sum owed when we moved

My room mate and I just moved out of our house and we are closing out all of the utilities. We were on budget billing with Laclede Gas and they are telling her that we owe $340 for March. This makes absolutely no sense to me. Why wasn't this evenly spaced out over months so that we don't owe so much and the amount seems outrageous anyway. We were there 13 months so why did it not even out? I cannot call them on this since it was in my room mate's name but this is absolutely insane. Has anyone faced this? Is this normal? I am in ultimate need of some poor skills help here. I am 7 months pregnant and not working and this is a lot of money for me. Thanks.
New and domestic!

New and domestic!

East Village Garden

East Village Garden

Wilt

Wilt

Step inside my room.

Step inside my room.

growing herbs from seed

growing herbs from seed

An ailing cactus

An ailing cactus