MTN wifi

My home wifi has not been working for a month now. Whenever I call the network they told me that I just need to wait it out. I got tired of not having any wifi and I decided to cancel. They informed me even though they're unable to fix my issues, I need to pay R1500 to cancel a wifi that is not working. I am then told I have to go to a local MTN to complete the cancelation and I do this. At the MTN store, I am told I need to call back the customer line to complete the cancelation. I do this and they tell me that they do not do cancelations on a weekend. I tell them I will be unable to cancel during the week because I will be traveling abroad, the lady drop the line on me while sounding very annoyed. To this day, the line is not canceled, the wifi is not working still, they have taken the R1500 and I am paying the monthly fee for a service which is not working.