Defender Direct Security ADT Bogus company, deceived, lied, said anything to get the contract signed! Indianapolis, Indiana

I had used ADT Security before and moved without a problem as they understood.   It cost $29.00 per month.

I called ADT (thought it was ADT) for a new system.  Defender Direct showed up and pretended to be ADT!  I questioned the guy over and over.  He assured me it was really ADT.  The cost was $39.58 per month.  I could not believe the cost difference.  I signed a contract for 3 yrs. on 8/5/10.  He said if I moved, they would "work it out." 

Ironically, the "real ADT" called me a few months later to sell their service.  I found out that I did not have ADT service, and if I did, it would have been $29.00 a month! He said he could not change the service since contracts were involved. 
 
I moved out of state and closed the account, paid to the date.  In March 2012 a collection agency/attorney called me.  He would not tell me anything except that he wanted  Defenders $658.00 and if I did not pay, he would send it to the credit bureau! He spoke in a deep voice and was menacing when he called!  He would not discuss anything except that I should pay up!  He knew my credit score was over 800! He threatened to ruin that and he did!  They sent the debt to Experian! 

I thought the court ruled that one could not be charged for services of monitoring not received.  I must be wrong.  How can I resolve this without paying what I should not owe?