Horrible service ever from cartrack

I've experienced horrible service from cartrack, since November last year the device installed by them is not working but every month they debited my account, on September this year they sent their technician to sort out their mess but the following day their device was not functioning again when I called they did concede it ever since they solemnly called me to arrange for technician to come again. I'm now ****ed with the service they never rendered and now I'm demanding all the money they've been debiting in my account.

Regards

Brian Mudzuli