Waiting for Cell C to call for SIM Swop for days

I was eligible for an upgrade on my CellC contract and received my new phone only to discover that it required a nano SIM card. I therefore required a SIM swop from my current SIM card to a new nano SIM card. I put in the request on Friday at 8:15AM and apparently the SIM swop people have to call me on a non-cell number at any time of day. So I must wait all day at a landline for them to call. Which I did and they didn't call. Then on Saturday morning I phoned the CellC customer service department to complain, to be told that the SIM swop department was closed on weekends. After being told that nothing could be done until Monday, I gladly left the prison of my home. When I phoned them this morning, I was told by a very surly and contemptuous \customer service"representative that I had missed the SIM swop call on Saturday. I have now spent six hours sitting at my desk waiting for the SIM swop call and nothing has happened. They will not give me a time when they will commit to calling me or a number to call them on. How is a SIM swop supposed to happen? This does not seem to be a very practical policy of conducting business or treating customers. What about customer service?"""