No network for more than 2 days and they tell me to pay for a sim swap

When I walked into work Monday morning(16/10/2016) I realized that I had no network on my phone. I switched off my phone a couple of times but it didn't work so I decided to go to the Potchefstroom branch and I was told I need to make a sim swap and I ask is it going to be free? because I can't be paying for something that is not my fault and the consultant said I will have to pay for it. My question still remains... Why must I pay for something that was not my fault? I can't be dealing with horrible reception and still have to pay for things that are not my fault!