Impossible contract cancellation

I have been trying to cancel my contract and close my account for several days now. The first time I called it took nearly an hour to get through to someone in retentions, the agent then informed me that I had to pay a cancellation fee in store. I then went to an MTN store where they let me know that the agent I spoke to forgot to put a note with my account indicating how much I had to pay. This meant I could not pay the fee and had to wait for a weekday to call retentions as they are not open on weekends. After finally managing to get hold of them and pay my fee in store, I am now unable to reach retentions. I spend 40 minutes on hold only to be told that the call centre is closed. Surely retentions should be making some effort to try and retain customers instead of pushing them to leave MTN even more urgently.