Paying for something that is not WORKING!

Started, going to Germiston fitment centre, with a very rude lady, not only being disrespect to my boyfriend, but other customers as well, absolutely appalling, maybe the lady in question should be trained as to how to work with customers. Had the fitment done, a few days later I called to test my netstar and I was told it was not working. The second they came out to install a unit, I called AGAIN to find out if it was working the day after it was installed, and once AGAIN, it was not working. They want to arrange to get it fitted for the THIRD time. AND, I am expected to pay at the end of this month for something that has not worked since the beginning, so is this **************** or is Netstars technicians just not trained properly? Why is it the customers job to test whether the **** Netstar install actually works? I do not want this from you guys anymore, come take it out of my car and forget that I even agreed to having it installed, as you simply cannot charge a customer for something that is not working due to incompetence of Netstars staff. Third time lucky, no, third time luckily lost a customer.