Accounts department

My name is Mandy Moodley and I have had constant issues with the accounts department. I have called 3 times after recieving countless sms's and e-mails for payment. My med aid paid according to the scheme that I am on. Your accounts department incorrectly billed. I have been trying to explain basic accounting to your EXPERTS and they do not seem to grasp the concept. It's simple, adjust your statement and make amendments to the correct billing scheme and then you should have a nil balance as the med aid has already paid you. Please advise short of trying to explain for over 10 min should I come to your office and adjust it myself? These tests are part of my chronic, and I am afraid that should this issue not be resolved that I will have this battle every 6 months. Please advise urgently.