Change of option without authorization

I took a medical on behalf of my son Ntshepe Solly Hlaka and I pay for it. His option has always been lower at R 615. His option has been changed to the highest at R1643 without his consent and without his permission. I now have unnecessary stupid and high arrears which he never authorized as he has to complete a form for change of an option to a higher amount. Can Bonita's explain who messed up here as my son earns way less than R 5000 per month hence we chose a owner option and why I am paying for it. Again he hardly consult any Drs but someone chose to be careless so that he can loose his medical aid. I am so tired of Bonita's' carelessness and can someone please sort this mess urgently.