Poor service manager

Today I took my car for service at Nissan in Vereeniging at around 6:55 am as they start working at 7:00. I waited for shuttle for 40 min. They sent a login link to check how is the workshop progress at 09:15 which I tried to log in but no luck. I rep**** to their WhatsApp account to notify them that their link says its not connected and the jobcard number is unavailable. They never read the message. At 14:00 I called the branch to find out how far are they with the service. Only to get a response that says they are waiting for authorization. From my side I called the service provider to understand what's happening only to find out they haven't called the service provider for authorization. I called them back an the lady by the name of Bianca she was busy to respond to my quiery. After 30-40mins she called saying just now they got authorization after 14:35. At 16:00 they called an say my car is almost ready and do I need a lift from home and I said I'm sorted. I got to Nissan branch at 16:50 finding my car parked outside so I walked in to get keys and they sat me down an said they will attend to me in few minutes. When they attended to me Bianca said my is not ready they never got chance to service it as they are short staffed. I asked why didn't they communicate with me immediately when they saw that it's not going to be possible to service my car. They told me they had 3 meetings that they were attending and their system was on an off and they have 2 Technician on side where as I was the first person at the dealership to bring the car. Funny enough the white guys that came after me in the morning they were not there on collection meaning their cars were done before my car and they came after me in the morning. I asked how do they operate and the answer I got was first come first serve but in my case was the opposite. I believe it's their way they treat black people like that as I asked few people that brought vehicles for service there.