Deliberate blocking of customer sim cards by cell c to increase revenue

I had a terrible weekend, thanks to cell c. My sim card was deactivated on Saturday and I contacted the call Centre to find out what was wrong. I was given a code to dial on my phone and at that time my phone kept giving me a response that I had been barred. I called the call Centre back and they told me I'd have to go to the technical department. Each time the agents would transfer me I would keep getting disconnected. I was unable to make any calls or to receive calls the whole of Saturday while my phone showed that I had network but couldn't make any calls. On Sunday my phone didn't have network at all and I called the call Centre for assistance and I was advised to do a sim swop. The agents told me I'd have to pay because my sim was damaged. I haven't damaged my sim in any way as I started using my sim in my new phone from 23 November 2018 and have never removed my sim card since. What I cannot stand is the fact that after doing the sim swop and being quoted a price I was able to use my phone normally. Cell C is playing games and I believe that there is some foul play on their part. This was a ploy to make more money by getting me to pay for the sim swop. I am totally disgusted with Cell C. This is no way of treating a customer and I would like that sim swop fee reversed for me to continue my existing relationship.