Poor feedback and service

About 4 months ago I upgraded to a Iphone 6 plus. What a mistake since the start I have been having problems with the reception of the phone. I am unable to use the internet and the phone keeps on dropping calls when you do have reception. On the 20th of July 2015 I took my phone into the Vodacom shop lakeside mall and they sent the phone in for repairs. On the 21st they notified me the phone is ready for collection. When I went to fetch the phone on the 22 of July it still had the same problem. They then sent it to the advance repair center and I was notified on the 30th of July to come and collect the phone yet it still had the same problem. It is now the 4th of August and until now I have not heard a single word about the phone. They said they were going to request a hand set swap. After dialing the 082111 number and holding on for 15min I was told I needed to phone Vodashop Lakeside mall and their phone just goes to voicemail??? What has happened to the customer comes first. Can someone at Vodacom or Vodacom Lakeside mall take some responsibility!!!