Do not buy from Mercedes Benz they are money hungry wolfs

I found a letter from the Attorneys used by Mercedes Benz saying I owe Mercedes Benz an outstanding amount of R10850.00 after I cancled my agility contract with them, gave back the vehicle and PAID the R10850. I owed to damages and milage on the vehicle. I even got an email from them acknowledging that they received my payment and that they received my proof of payment. Yet they come back to me 6 months later saying I owe them that amount of money. Sounds to me someone is *********** of doing their job at Mercedes Benz. So I ask how many other *********** people work for them.