Appalling, bad and terrible service rendered by Mercedes Benz representative - United Motors Secunda

I want to register my dissatisfaction and utterly disappointment at Mercedes Benz South Africa for allowing companies such as United Motors Secunda to render service on their behalf. I took my car in on the 26 November 2019, at 07:30 and the car was only attended to at 16:00, the service was rushed, the car was released after 18:00 and not washed. My wife had to sit for 3 hours waiting for the car to be attended to. I will never ever take my car to Secunda United motors, they don't understand the meaning of professionalism, the Quality of service to be rendered and treating customers with respect, I wonder why companies like this exist. I'm really shocked how a company like this can be associated with Mercedes benz brand. This is very appalling to say the least.