MTN Cancellation Policy is absolutely terrible!

II am absolutely furious about MTN's cancellation policy! I purchased a router in Upington, Northern Cape, while working there, and later moved to Johannesburg. When I tried to cancel the service at the MTN store in Fourways mall, they insisted I return the router to the Upington store where I bought it, even though it was one of the MTN shop. They refused to take the router back. Now I'm stuck with this useless router, paying for a service I no longer require, and receiving zero assistance from MTN. This is completely unacceptable!