Refund still not processed ...22 dec still waiting

I bought a trade in iPhone. The battery didnt last more than 2 hours, so they swapped it with some shocking looking phone tgat looked like it had been thrown on a wall a few times. So sent that back and asked for a refund after losing trust in their products an service. I have been waiting for a refund of R2500 since 22 Dec 15. I was then promised that it would all be refunded by today but surprise surprise, nothing happened. What absolutely **** service. And to think Im dealing with the manager there!? Seriously? Disappointing that you don't care about your customers.