bad client service

On the 26th of November 2015 @ 5 o'clock I received a statement from the doctors stating that I owe them a large amount of money from 2012. I never was once called or sent invoices on of these doctors appointments and have been to the same doctor after all of the charged appointments and I was never stopped in their offices or notified to be informed that I owe them money. I have spoken to my medical aid whenever I get a invoice and even then it was never brought to my attention that I owe the above mentioned doctors money. Sadly I'm not the only one who got a statement and this is a problem on their side because their accountant or clerk did not do her job and now I have to suffer the consequences for her failling to do her job in the correct way. I'm upset but surely have learned my lesson by not making use of their services again in the future.