Netcare Umhlanga Over charging admission fees

Netcare Umhlanga overcharged me for my admission to the hospital. I was supposed to pay a shortfall of R1730, however, Netcare Umhlanga charged me R4920. My Gap cover picked this up for me when I submitted the claim. I have contacted Netcare Umhlanga on multiple occasions and still haven't received my refund. When checking into this hospital, make sure you double-check that you aren't being overcharged. Sadly, you'd think when you're told a certain amount has been authorised by medical aid and what the shortfall is, the hospital wouldn't be trying to **** you and take extra money from you and when you try and get a refund from them, they couldn't care less. 2nd June - admitted into hospital for an op 3rd June - discharged 6 July - I requested the statement as Gap cover picked up Netcare Umhlanga overcharged me. 26 July - I received the details from Netcare Umhlanga on what I needed to do to get the refund 28 July - I completed the documents and submitted to Netcare Umhkanga 1 August - I followed up. No response 4 August - I followed up. No response 10 August - I followed up and called, and only then did I receive a response saying the payment would be made the next day (i.e: the 11th of August) 15 August - I followed up again as the payment still hadn't been made. I got told the proof of payment would be shared shortly 16th August - I followed up. No response 17th August - Still no payment.