Dstv doesn't want to pay my refund

On 1 September I over paid dstv for the amount of R860 and I app**** for a refund and sent the documents they asked for proof of payment, customer service number and etc and I was instructed to wait for 14 days so they can finalise and process my refund after 14 days I informed that I haven't received my money yet and they informed me to wait for another 14days dstv is ****ing us i want my money back they can't do this to their customers and get away with it no ways and I noticed that they credited my dstv account and with R860 and they now are deducting my monthly payments from that R860 which we didn't agree upon that I want my money back