mtn uncapped home wifi is inactive but I paid for it

I bought the mtn uncapped home wifi and when they delivered it they said the sim card was going to be active the following day. bear in mind I already paid for for the months ahead and 2 weeks as they instructed. the sim was never active and I called their customer care number 135 and they said I must sent it to my nearest Mtn outlet of which I did and they told me to call the same 135 number and ask them to collect it as they cant help me. I sent them emails since I couldn't get hold of the consultant on their customer number and had no other direct number. its been a month now and they now they are telling me to that it has a soft block because I am owing the monthly instalment of R243 and to use the wi fi cell number on the sim card as ref and I am unable to get it because it was never active. I don't know what to do anymore because I asked them to come collect it and cancel the contract if they can't activate it and they did not. I requested that they call me and they never call nor resolve the issue.