Faulty unit no help no refund!!!

Cartrack installed a faulty unit in my vehicle. My app actually tracks somebody elses vehicle. They never picked up on this untill I notified them more than a month ago. I paid almost R10000 for that unit. It has now been a month plus and it still isnt fixed. Promised me an urgent/immediate refund as I told them I was going to change to tracker because cartracks service was so poor. Now I am having trouble getting them to pay the refund. Keep telling me the money will be transferred but it never happens. Very very poor service!!!!