Poor service at Century City Mercedes

My car went in for a service on 13th January. I was dropped off at V&A Waterfront where I was going to spend the day to wait for my car. Dale was my Service executive. Normally they send me Sms's to update me on the progress. With this service I did not get any update. The driver phoned me around 3 to let me know that my car hasnt gone to the workshop yet and that he will unfortunately not be able to pick me up. I phoned Dale at 4 and confirmed that my car was in the workshop, but the wont be able to pick me up I then took an Uber to the garage. By 5:30 Dale came to me and apologised that the car has not gone to the workshop and that I will have to bring the car back the next day. He also said he was too busy during the day and couldn't update me on the progress As was not interested in his excuses and I had doctor's appointments the rest of the week. He then offered me a courtesy car which I could pick up the next day I had to fetch the courtesy car the next day, must add the lady dealing with the courtesy cars was very efficient and friendly I had to drop off the car again and collect my, do I had to make 3 trips to Century City from Durbanville and I had to waste a full day browsing around the V&A Waterfront I also asked Dale to update my navigating system. He 1st said it is not an approved Mercedes and quoted me like R28k to install a system. I told him it was a Mercedes system and I only had to buy a SD card. He the quoted me R3,500 to upgrade I was told at the time of installation I was told that they will update it 3 times during the duration of service plan. He promised that he will find out and let me know. Needless to say I'm still waiting for his call.....a month later. I was phoned to rate the service and I rated them a 1 and I told the lady in no uncertain terms how disgusted I am with the poor service I received She told me she will report back to the manager and I can expect a call from the manager. Needless to say I am still waiting Based on the poor service I will never take my car to Century City for another service. I would rather go to Paarl