Netcare Unitas Centurion review: I was made to pay for another patient now they dont want to refund me

On the 3rd June 2023, I was at Centurion Netcare Unitas hospital Emergency Department, I was made to pay for another patients bill while my medical aid paid 90% of the fees. I payed R948,50 instead of R34.50.

Now they do not want to reverse or return my money, they are saying the policy says I must wait for the medical aid to paid them 1st. This is confusing because the amount I paid is much higher than the consultation fee, is not the balance after what my medical aid authorised.

Kindy assist me with this matter.