MTN LTE Wifi

I have been trying for more than 2 months to cancel my lte data contract and my contract is ending on Friday

I send them emails without any luck and when I phoned 135 to speak to consultant I was told no they don't cancel contracts deals over the phone I need to go to a MTN store to cancel it. I went to the MTN store in Canal Walk I was told no they don't do it I need to phone the 135 number to do it.

I'm frustrated I don't know what to do and they will just keep on charging me.

I really need help