Poor Service, Bad Attetude and Unprofessional

Took my iPhone 6 Plus in for screen to be repaired on 19 Aug. Vodacom Repair sent an SMS on the 20th indicating that I could collect phone as it has been repaired. Collected phone and when tested when I was back in office it was faulty, took it back the same morning and they indicated that the software needed to be upgraded, I could collect the afternoon at 15:00. Arrived at 15:00 to collect just to find out that phone screen that was replaced was faulty - they did not even bother to call and just let me know not to come in to collect phone. I asked for the manager who was very unprofessional and not really helpful, after a huge argument he agreed that he would personally tend to my problem and make sure that my phone would be ready for collection on Mon the 24th, he even signed on my tax invoice (as I had to pay R3700 for repairs) that the phone would be ready on Mon the 24th. Its 14:43 and I still don't have a phone as I had to call to follow up just for Sean that promised that I would have my phone on today to tell me that the screens are on back order. Vodacom Repairs Alberton has my R3700 and I still don't have a phone. How do you make promise and don't stick to it. BAD