Netstar tracking - Harrassing me over a account

Netstar harrassing me over a account, i never had a netstar account, but gave me over to itc
Product/Service I’m complaining about...

I bought a car in august 2018 at , Mc Carthy nissan in germiston. It was a special on the Datsun go lux, part of the special i received 1year FREE insurance with bidvest and 1 year FREE tracker from netstar. All included in the deal. Did not sign anything by them, except for my car contract. After 1 year then i should decide if i want to keep the tracker and bidvest insurance or decide on other insurance. A month before it expired i phoned them and told Netstar they can come and remove the device from my car, we took out a new insurance from discovery. They told me that i dont need to remove the netstar tracker, they only switch it off. So then they phoned me and told me that i must pay a settlement amount of R600 and something amount. I phoned collen khubai at nissan, he told me there is no such account and should ignore it. He said it was part of the cars package deal and everything was cancelled after 1 year when the FREE insurance expired. Now Netstar keeps phoning me and gave me over to ITC. I dont have an account by Netstar. How can i pay something that doesnt excist. If you phone them they say sorry it will be sorted out but nothing happens
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