Bad service from beam telematrix

I have been struggling to communicate with beam matrix in 2018 regarding to the car tracker in my car. I called them 3 time they kept on saying they'll get back to me and they never call. The main aim was to upgrade the car tracker. Since they was no communication then I had to reverse when they debit, still they never call to ask what could be the problem. I sent them a cancelation later, they quik responded and sent a cancelation fee of R960. They didn't say how will I pay them, this was in October 2018.from there they kept on debitibg the normal monthly payments of which is R63 pm, I kept on reversing because I didn't know if they were deducting in terms of the cancelation fee or monthly payments there was no communication. So the money increased to R1200, I thought it was because I was taking time to pay them. I paid this amount in March. Then they continued to debit when I asked them they said I have to re write the cancelation later of which they give me a new amount to pay,they said that R1200 it was an amount that I was owing not a cancelation fee.