NHC no customer service

I have used NHC Bryanston about 6 times throughout my life. Due to being on a hospital plan I have always paid cash / card for consultations and medications for years. My wife and kids are on a separate plan. I was contacted by Lexmed a collection agency who were Instructed by NHC to collect monies from me in a consultation to which I did not pay Dr L Stockight. I told them misunderstanding and took the case up with NHC directly they told me that my account should never had been handed over and I have no outstanding monies owed. Lexmed told me it was for consultations on 2 dates in December 2020 I then provided my bank statement for those dates showing I had swiped my card. I thought the matter was at rest, after that I was contacted again and the date of the consultation to which I did not “pay” was changed I once again went onto my bank statement and provided proof of the payment. I have been black listed and JOHN at head office whom I have provided the 2ndbatch of evidence still has not returned my email or telephone calls. I physically went into NHC Bryanston to sort out this nonsense and was put through to John telephonically, I have since provided additional evidence pAyment and the drama continues. NHC you are terrible at not assisting customers, and my name sits with an unpaid consultation to which I have paid and always will pay.