Discovery medical aid has an awful secret clause. One that you never have to sign. You only get a judgment

I have been a member of Discovery medical aid as part of my employment with the Coca-Cola company. I have been moved by Coca-Cola to Thailand for a three year assignment. I have never personally paid medical installments to Discovery. It was deducted by my company off my paycheck. Discovery has blacklisted me an I am now in trouble with a judgment. My directorship at Metpack SA has been compromised as somehow they may not be paid by corporates due to my judgment. HOW DO I OWE THEM MONEY? Why don’t they explain this. I am very disappointed with their conduct and unprofessional approach. Please note my mobile number is from Thailand. Please add +66 before the number