MTN cancellations are the worst!!

I am so sick and tired of contacting Mtn. My contract is expiring soon and thus it's due for an upgrade. So since 2 months ago when i visited a Mtn store, i was told that since i do not want to upgrade and want to cancel, i must call the cancellations department 30 days before the expiry date which was end of August. So as i was told, i called end of August. I couldn't get through and waited for 20min before i cut the call. So i called the customer care and spoke to a lady who said im not supposed to call now, i must call to cancel end of September. Then few days after i get a call from Mtn to offer me an upgrade, which i declined and told the lady i would actually like to cancel and go on to normal pre paid. So she said well you should have called cancellations 30 days before which was end of August. So i decide to call Customer care yet again few days ago and the lady said she will transfer my call to Cancellations dep. I waited on the line for 30min and still hadn't received assistance so i cut the call as i was at work. Now, that waa my 3rd attempt to get through to cancelations and they just never answer the call. That is absolutely frustrating!! Firstly MTN customer care gave me different dates of when i should cancel. Then i called 3 times and the waiting period is nore than 30min. Ridiculous!! How is that even possible. If the cancellations department is so busy that your call is in the waiting line for over 30min, then i would say Mtn has a problem that so many people are cancelling. But i would like to know why it takes so long and still i haven't got through till today. How do i cancel my line? When you want a contract they contact you very fast. Why is it that when you want to cancel you can't get through.