Impossible to cancel contract and still getting charged 8 months later

I sold my car in August 2022 and I have been paying this matrix/mixy monthly subscription ever since April 2018 until now. I have called many times to cancel and when I ask for a reference I get told there is none. Then I called again and I was told I can only cancel after I pay the outstanding amount (I had been reversing the debit orders after the first time I called and cancelled). So I agreed AGAIN and paid the outstanding amount in March 2023. Then I paid a further 1 month at end of March thinking maybe thats part of the cancellation. Now I see I have been charged AGAIN at end April 2023. Please note that this Matrix debit order/contract ***gy backed against contract with Tracker. I had assumed that when I cancelled with Tracker that all debit orders would cancel but this one remained. Apparently that's a different contract that I was not aware of. So when you sign with tracker you have 1 contract with 1 debit order and then automatically Matrix/Mix charges you on a separate debit order( i thought it was commission for the middle man company who installed) Anyway now I am trying to get hold of them AGAIN at *** and only Option 1 works and that person cannot put you through to options 2 or 3. Option 4- customer care eventually answered and then put me on hold and then cut me off. It is impossible to get this contract cancelled. The one time I chose the option for cancellation of DEALER-VEHICLE SOLD and was told that this was wrong option and i should have gone further down to option VEHICLE SOLD. There are at least 30 options to choose from when trying to cancel. Please make sure when you get a tracker as THIS company ***gy backs and you will really struggle to cancel. I have now paid R586+ extra and am still unable to cancel this contract that I do not need and do not want/ They are also not doing any work for this as I do not have the car anymore. This is an ********* company who uses complicated cancellation procedures in order to take money from you for services they do not perform. So it appears that's how they make their money. By charging for cars they no longer track or whatever it is that matrix does because honestly I still don't know what their link is to the tracker that i installed, paid for and subsequently cancelled when I sold my car.