Refusal compensate customers for purchased Walka devices

DSTV recently decided to discontinue their Walka service and refuses to refund me for the device I purchased because I didn't take out insurance on it. Because of this I have decided to also cancel all my DSTV services and use Netflix as most of my friends and colleagues already do, but still think that is my right to demand a refund on a device I purchased if the service is discontinued.