Incorrect info given

My medical aid has a postnatal benefit for a check up with a GP or gynae. When I went to my gynae for my postnatal checkup I called discovery to confirm this benefit and to obtain the codes that the doc would have to put on his invoice. The lady I spoke to at discovery stated that there was no special code and confirmed on the phone with the finance lady at the doc's office that the normal codes that they had been submitting would suffice. To my surprise when the claim was processed, it was paid from my savings and not from my benefits, I again called discovery and this time the consultant I spoke to provided the correct code that was supposed to have been on the invoice and indicated that the doctor has to amend their invoice and resubmit. The doctor has already been paid so he has no reason to submit an amended invoice. The problem was caused by the consultant who told me that there is no special codes and I need discovery health to correct it.