Worst service

I am very annoyed and disappointed with the service I receive from Car track. In December 2019 I was debited an amount of R665.25 but my monthly subscription is R120 a month. I sent a request for a refund and cancellation of my subscription in January, to which I received no response. I received a form that I needed to complete for a cancellation, which I sent back on 20/02/2020 with all the completed information. Still I have not received any feedback and I am receiving messages that my account is in arrears. Firstly I don't understand how I can be in arrears when there's always funds in my account and the premium is paid through debit order. As far as I know I am supposed to receive notification if the debit was not received and if the amount of R665.25 that was debited in December was the arrears, who gave you the mandate to debit that amount from my account?? It's April now and still no response or any communication or confirmation that this subscription has been cancelled.