ALLOW ME TO CANCEL MY CONTRACT!!!!!

MTN is just refusing for me to cancel a contract due for upgrade (which I do not want). I have been trying to call them since beginning of the month but soon as they say they are putting me through to the correct department my line cuts and I get an sms saying my matter is resolved or the line continues with no one on their side!!!

I am fuming as now they have even credited me despite my numerous attempts. I WANT TO CANCEL MY WIFI CONTRACT, it is extremely expensive!