AEP Energy Based out of Illinois I received an excessively high bill from AEP Energy and repeated attempts to resolve it have been ignored. Chicago Illinois

I received an excessively high bill from AEP Energey in July in the amount of $338.56.  After I paid it, I decided to cancel the service.  When I called customer service, I specifically asked if there would be early termination fee and was assured that I had met my contractual requirement as of June.  The first "final bill" I received via e-mail was for $741.46.  Within the next few weeks, I recived a bill for $818.21, $859.76 and $977.76.  I have contacted this company on at least 7 separate occasions in an attempt to resolve this issue.  The first time I called was on 08/12/14, then I called on 08/13/14, and again on 08/18/14.  The first time I called I was told the "system was down".  The second time I called them the customer service representative refused to transfer my call to a supervisor and the third time I called I was placed on hold for over an hour.  So then I followed up with two different e-mails.  This resulted in call-backs from the customer service managers, with promises that they would look into it and get back to me.  To this date, no one has gotten back to me or attemptted to resolve this bill.  And I continue to get e-mails with bill amounts going up each time.  I probably need a lawyer, but thought maybe six on your side could help.  Plus, I thought I probably wasn't the only person this was happening to.  Thanks.