Overcharged on an account and now have to wait until Jan 2018 for my refund!

On the 5th and 6th December this year I had 3 different radiological procedures done at Diagnostic Radiological Services Inc at Sunward Park hospital. I had to pay an upfront co-payment of R2750, which I paid before the first procedure was done. After the other 2 procedures were done I was told there was a short payment on my medical savings account of another R1534,74, which amount I settled immediately. Now, almost a week later I get an "account or member statement" showing that I am due R1499,03, BUT NOW I HAVE TO WAIT UNTIL JANUARY 2018 TO GET MY REFUND AS ALL "MANAGEMENT" ARE ON LEAVE. This is shocking, considering that they made me pay upfront and now I have to wait for them to refund my money. Disgusting service.