Month to month contract

I am dissapointed with Tracker, I had a 36 month contract which is now finished, and i was on a so called month to month contract in which i am entitled to cancel at any time, I did so around May month , to reopen afforable one in which i did, i was contacted by the fitment centre in Krugersdorp to make an app to remove the skytrax and put in the devices i reopened, but that never happened as i was told the Technician was off sick and they will revert back to me in which they didn't as its their responsibility, according to my knowledge the month to month contract was cancelled , to my suprise, i receive calls telling me that i am liable to pay 2 x premiums for May and June, of which i dont know where does that come from. they then handed my account over to Norton attorneys for R498, which equate to the May & June premiums, I then called them on the 12 August to find out why my acc was handed over, Mathebe (consultant) told me i am liable for those two payments whilst i cancelled the contract, she told me about the terms and conditions clip of the month to month contract. i requested them to send the recordings before a can make any action, i am still waiting for those recordings..