Poor service

I kook my car to Audi Umhlanga the for a squeaky noise on the breaks. I was told that the front brake pads need to be replaced. I was told they were replaced(I hope so coz I was never given a printed job card of what was replaced)). Rear breaks were inspected, I was told they were within the recommended spec. I collected the car, the squeaky sound was still there. I reported the matter., I was told to bring the car again which I didn’t. Shouldn't they test drive the car to make sure the issue is resolved before calling the customer for collection. I was told to either take the car to the car wash to spray gun the dust or use a blower from the gas station to blow the dust. Really ! I am not a mechanic but that was the dumbest advice to give a customer or anyone for that matter. The noise is still there. I was told that they need to ride with me so that I can tell them where the noise comes from. They are using me to make their job easy yet they are called “engineers” or experts.I wonder if they know what they are doing or they just follow the manual/troubleshoot book without using their brains. I promise you, if the car was out of warranty they could have quoted me thousands of rands to replace the “suspected” parts. I don't trust their workshop. This is not the first time Audi does this.