Terrible service from no less than 5 staff

My daughter was born on 10 Sep 2014, there were various complications and she spent 3 weeks in ICU. Needless to say this was a terrible time. Since then various bills keep being sent which Discovery has not settled. Over the last 9 months I have managed to get Disc to sort them out. There is one however, which I have called no less than 10 times to sort out. Various staff have made promises to call me back, none have. I called last week and said that if my problem is not solved, I will take start with social media. It was for 2 in hospital expenses for a Dr on about the 13th Sep 2014. Total R1600. The doctors accounts dep have called and threatened to blacklist and been very rude. I am appalled at this. I have been a member for 15 years. Worst service i have ever had. I have explained the same story no less than 10 times. Each person says they will sort it out. None have. I am absolutely fuming. Discovery is not a medical aid, it is a marketing powerhouse who happen to sell various insurance products.