Nicor Advanced Energy Overcharging customers! Naperville Illinois

We signed up for Nicor Advanced Energy as an alternate natural gas supplier when we first moved into our house in 2009, under the assumption that it would save us money. It does not. Over 5 years, only three months offered prices lower than Nicor's regular pricing. The other 57 months, we have overpaid by over $800! We never would have known, but we got a bill last month almost double our highest ever bill, around $336. Yes, it's been cold, but when I did the research, it turns out they were charging us about 55 cents more per therm.

Obviously I was upset, and cancelled my service with them, which would not switch over until the end of the month. Which meant they had one more month to screw me over. Just got the bill today, $498! For less therms! They jacked up the price to over a dollar more per therm than Nicor directly. Ridiculous. How is this legal?

Avoid at all costs.