Disgusting accounts service

My son had an operation done in June 2016 at Hillcrest Private Hospital. Two surgeons were operating at once. One surgeon was covered by Medical Aid and the other not. We paid cash in full and upfront for the hospital and the second surgeon on the quotation that we got given by the surgeon. The hospital then proceeded to claim for both surgeons from Medical Aid and reimbursed us our paid hospital bill (after I told them that the second surgeon will not be covered by the Medical Aid) just for the Medical Aid to reverse the payment for part of the claimed amount. The hospital then sends us a bill which is R5000 more than the quoted price. When I asked them for an itemised bill of the outstanding amount I phoned the Medical Aid to check that all the correct codes where paid and most of the codes on the bill had already been covered by the Medical Aid and we where being charged for them again which according to the Medical Aid was *****. I went into the hospital and explained the whole story to the accounts lady (which as always she wasn't the one working with the account but the person that does wasn't there) and she said that she understood and that she could see there was a problem and that she would refer the matter to their Accounts Manager to sort it out. So after numerous emails and reminders (we are now 15 months into waiting for the correct account) I STILL don't have a correct account just to receive an email today asking us the settle the initial (wrong) amount!?!?