Cartrack worst service

Last month I stopped my debit order on cartrack because my contract of 3 years ended. They called me last week stating that I owe them money because even though the contract of 3 years are finished it goes on month to month afterwards as per their terms and conditions.I checked those terms and it states that they will let you know in writing no less that 40 days prior to the contract ending if I want to renew or not,after that letter they will go on with a month to month contract after the expiration date. I nevrr received such a letter because I would have ended the contract now they are hasstlong me for 2 months installment. Very bad service.They called me now again and the lady I spoke to last week said that the conttact is finish I only need to pay the 2 installments.Today they told me that it was never canceled she put me through to the department where I must canceled. Call went through but I was cut off so I still dont know what to do.