Fourways bmw /cedar isle ****mers

I took in my car at Fourways bmw in the morning for a door lock replacement and I was promised to be updated on the status of the repairs and the so called diagnosis and that did not happen until the next day when I was told that they will only be diagnosing the car then in the morning of the 2nd day, subsequently I was quoted and accepted the quote therefore giving them permission to fix the car. I was then shocked by them telling me that they will charge an extra fee for doing the diagnosis.. Why charge me for the diagnosis of something which I told them was a problem in the first place? Why charge me the diagnosis fee when I still agreed for them to fix the car? I would justify the so called diagnosis fees if I had refused them to fix the car.... Their attitude is just a ****. It's just pure *******.