USELESS MTN

In mid may I have received a call from mtn consultant there were offering me a sim card for data ,I took up the deal without being told that I cannot use the sim card on the phone,I tried to use the sim card I receive emails saying my phone is not compatible with the sim card. I call mtn to inquire I was told that the sim card can only work in a router,I went to buy a router when I insert my sim carrmd is still not working in the router,I went to mtn store they told me that I need to call Online activation ,I called them abd they said the sim is now activated and Ricaed,when I try to connect the sim is still not working ,When i call again no one knew what could be a problem until today I called again the lady said there were some restriction on my sim she is going to remove it,She did remove it the sim card connect for one hour and disconnect again,I have to call mtn again the guy who was assisting say you are using the wrong router,The sim card can only work in specific router How I am gonna know that because even the sales person never tell me about the router issue,If he raised the issue I would've bought together with the router,Now they said I need to buy another router imaging I am not happy about the service I have received from MTN Since sim card was delivered in may toda is the 25 june It's still not working and I have to pay the installment?Never Its possible that i can buy another router and sim wont work

So I would like to cancel this contract without any penalties because,You never provide the service to me