Charged with penalty fee for cancellation

I was on contract with Rogers from sept 2009 to sept 2012 with a very good plan for just $20 for almost 8 years. I confirmed and called them in July 2012 when I received a bill of $40. They said its because my contract plan ended now and I am on regular plan now. I said I have fido plan their contract ended but price is still same. Rogers rep said my contract ending in sept 2012 when I asked when I can cancel it without penalty. But could not understand by they removed my special plan and put me on higher plan.
So I called in sept 17 to confirm again rep said sure its out of contract and you can move on. So I moved on to chart wireless but after a month I got $90 bill from Rogers for canceling now they say it is because I cancelled before oct 29.
Wtf.  Their rep gave me wrong info. What's my fault in this ?????
Now their cust relations said come back and we will waive that fee. But plan will be $45.

Manjit