Forced to pay for a contract I had requested to be cancelled.

I got a car tracker into my vehicle three years ago but this year 2018 in April I cancelled the contract because I was no longer working but the tracker was never canceled. I received an email in June 2018 to say the account has been handed over to the creditors. I called the manager of netstar at their offices in PE who emailed me and said the contract was not cancelled when I requested to cancel since the three years has not ended. I told him I was not working hence I cancelled and I also requested the contract. I didn't hear anything from him again. I received a phone call again from the creditors again who said I needed to pay about +R700 and I told them I had cancelled. The matter was referred back to Netstar,they emailed me to ask me if I still wanted to cancel and that if I did I needed to pay +R 170 for cancellation fees. I rep**** to say yes I wanted to cancel as I did in April and I asked them to explain why must I pay because there was an instalment dedicated when I had cancelled but there was never an answer. Now I'm receiving more phone calls from creditors to say I need to pay +700 and this is affecting my credit status. I need help because I'm not working hence I cancelled the tracker in the first place.

I've tried calling the head office at netstar but I end up wasting money on airtime because there lines are always busy.

Please help me.

Regards