Cartrack from hell

cartrack is harassing me to pay R278. I have been using cartrack 5 years with no joy. i am being bul**** for cancelling their service over the phone due to lockdown. they will call me 5 times a day. i have sent cancelling letter but still they are adding more fees. i asked them the initial contract and recordings to send to my attorney but no response from from them. even after sending the cancellation letter they sent me to pay R418. so frustrated and upset