Direct TV directv charged for a contract they broke Y???? Internet

Directv is trying to charge for cancellation fees $450.00 when I had their service for 6 weeks when I got  shut off   I can never get a supervisor on the phone and they are the ones who broke the contract to begin with by not honoring my rebate after I talked to ther rep on the phone and he said go online and sign up for the rebate then call him back I did and the rep said I was all set and my first bill would be 34.99 plus taxes I live in mass and the taxes are high here but I got my first bills at 1 week of service in the amount of 68.93 that is almost double what I was quoted they didn't give me the rebate I have called and called never getting anyone that knows crap and they are hiding the supervisor because he/she is to scared to talk to anyone cause that company is a damn rip off they broke the contract first and I have to pay for their stupidity when a person or comapny breaks a contract shouldn't it be null and void on both parties side I would think so I may need to get an lawyer also I never saw in writting that there is a 450.00 cancel fee nor did I sign anything quoting that where are my rights as a comsumer and since when is getting cable a credit towards your credit report they shouldn't be allowed any where near my credit report