Sim swop nightmare, why did I choose Cell C again?

We have recently upgraded our contracts. Our new phones requires the use of a smaller sim card and we need to do a sim swop. My husband is the account holder and have tried 3 times without success. The first time the call centre was offline the second time he battled through a huge amount of security questions after which the agent told him that he is in the wrong department. He was transferred, battled through the same questions, another set of security questions, was asked to hold on to complete the transaction via an automated system and was cut off. He phoned back a third time, was transferred two times and succinctly warned the agent that he was cut off previously. He again redid the same questions, again held the line and was again cut off. I am so irritated to be stuck with cell c's incompetence for another 2 years.