Supersonic pathetic customer service

Supersonic is the most unprofessional ISP ever!.Their whatsapp service is useless, you hold on for calls to be answered for frustratingly long periods of time. I am seeking a R449 refund and gosh it's like asking them to "dig up a gold mine' I, in error made a double payment, even if they don't give my money back, they do not even give me an option of using that amount as a credit for my next payment. This is happening since 6th June 25. I have called them so many times and I am always told "it's with the billing department " and then they will get back to me. Even their Manager Muneiwa, whom I had a bit of hope in! .I am still awaiting his call!..customer service should be the utmost priority of.any business., customers are your business , clearly Supersonic does not care about their customers. This will be your downfall Supersonic. Unhappy customers will move on..