Terrible Service, and able to track someone else's vehicle.

I have been trying to get a tracker installed in my new vehicle and the technician was scheduled to come and do the installation last week. The technician did not show up, no tracker was installed, and when I called I was advised that they will follow up and get back to me. Since last week I have received no feedback whatsoever, and when following up on their official WhatsApp chat I receive no response (also since last week and again this morning). Most concerning is that they have billed me, and on the app the new vehicle is reflecting, but at the totally wrong location, which leads me to believe they have installed a tracker in an entirely different car which does not even belong to me, but which I am now able to track (this is almost certainly a breach of someone's personal information, as I am now able to track their vehicle's whereabouts, so there may be some significant POPIA implications here). I need them to contact me with a solution and install the tracker in the vehicle today, otherwise I am cancelling my contract which includes another car too.