MTN Store - Elridge Corner ****** me!!!!

The MTN Store - Elridge Corner in Bartlett Boksburg ****** me! I returned their router (month to month home internet) on the 30th on November, but they neglected to follow through with cancelation of services, which led to me being charged while not using their services. When I claim my money back, they give me the runaround. A lady by the name of Desiree in that store is responsible for this whole ***** up but she won't own up to it. Is MTN in the business of robbing customers now? This is unacceptable. It's my hard earned money and I want it back!!!