canceled medical aid without consent

I had my medical aid though my company and resigned and moved to a new company, Discovery cancelled my medical aid and when I contacted them to reinstate my medical aid they said I owe them money for usage from my medical savings account, now why should I pay for cancelation penalties if I did not cancel my medical aid? Should I not have the option to continue my medical aid. now on the phone with the call centre be pushed from pillar to post. clearly I am not good enough to be a Discovery health client. oh by the way still on hold and 26 min in on the phone.