Cancellation of contract

Hi. I have for 2 weeks been trying to cancel 2 of my contracts. The only reason i want to is so i can keep the numbers as a voice line and move it to prepaid so i can take up 2 new data contracts. But after the pathetic service and waiting on the line for 25 mins or more and eventually cutting the call i am really considering cancelling altogether and porting to another network. This is really horrible customer service and all the complaints about mtn here should open peoples eyes on how disgusting their services are