Bad customer service

I bought a car in 2017 and also took out a car tracker with netstar. For personal reason I defaulted and informed them that they may double deduct my account. But they failed until they handed over my account and suspended my account. Upon payment of the required amount, I took the contract as being canceled as I had breached the contract. After paying, they indeed never interacted with me, until they came back again saying I owe another money. I contested this until I gave in and paid once again and this time I sent numerous emails canceling the contract and they ignored me, no reply whatsoever. Today 30 October , I phoned them around 11: 30 and asked for cancelation but the lady wanted reasons for cancelation, I told her that I don't have reasons, I just want out. She insisted on the reason until I can out of airtime. She promised to phone me back, I don't want their calls, I want out that's what I want and I'm not changing my minds.