ER consulting has put me off using Mediclinic for life

I took my child to sandton Mediclinic in August 2024. I paid for the visit in full at the time but then months later started to get requests to pay the account I had already paid. After sending proof of payment several time I was told the account was cleared only to be send loads of threatening texts every day for the last six months saying I owe ER consulting. The amount has changed from R300 to R500. I have emails from Mediclinic saying it was all paid at the same time. I’ve sent countless emails and made calls all to no avail. I’d happily pay R500 just to have this harassment stop but I have no faith that doing so would make any difference