Ster-kinekor terrible at customer service!

I made an online booking with Ster-kinekor. I had the date wrong and immediately sent them an email to try to refund the booking. They asked me for some information in order to process the refund which I sent to them and asked for confirmation that they received it and to let me know if they need anything else. I haven't heard back from them ever since. I sent 4 emails after the original email. I phoned once and they assured me that the refund will be processed within a week. I is now 3 weeks later - no reply from my emails, no refund! They are happy to take your money for a booking, but try to get a refund...it seems to be impossible!