Mercedes Benz has become a JOKE

To say I have had it with Mercedes Benz and their service is an understatement. My first problem with MB Pinetown started in February when I took my car in for service and it wasn’t only to find out in August that my car was never serviced and my extended maintanance plan was almost cancelled even though I was told to come fetch my car 2 days later that it is ready. Fast forward 8 days and a million calls later my car was serviced. Fine. Last week on the 6th of October as I started my car in the morning to go to work, my car wouldn’t start and displayed a message across the screen which read ‘without geat changing, consult workshop’. I called Mercedes Benz Roadside Assistance and they came to tow my car to the nearest dealership which is Pinetown. I called the dealership around midday to find out if they have received my car yet and they said yes they are going to start on it. The following day Wednesday 7 October I called again at 9am to ask for any progress and I was told the technicians need my permission to take apart the wiring and it will cost me R1500 and I communicated that I am on an extended maintainance plan so why should I pay, it is only then that they checked on the system with my car VIN number. Late of Wednesday I was told that the car is starting again and the gears are changing and they dont know what the problem was because they didn’t fix anything and now its miraculously working. They said they still need to look into it. On Thursday morning I was told that they are going to take a 30km drive with it and see if it gives the error again and that the senior technician has also looked at it and couldn’t find any problems. At 3pm Thursday afternoon I picked up my car. On Friday I went to work as usua and on Saturday I went to the shops and came back. Today 11 October as I was starting the car it showed the same error message it showed last week Tuesday ‘without gear changing, consult workshop’. I am not confident about the service MB has given me thus far and they will keep my car and come back to tell me the do not know what the problem is. My question is doesn’t Mercedes have a research unit or query escalation line because it does not make sense to me. The MB policy clause 4.15 on maintanance plans state that if my car is kept by Mercedes for more than 48hours I am supposed to get a courtesy car but in all the time I have been having these episodes with MB, I have never been offered a courtesy car and they always keep my car for more than 48 hours at a time. I am honestly losing trust in this brand. This is frustrating!