No help

my car a CLC 350 went for major service on the 26/05/2015 since then the car has been making very loud embarrassing noise when i hit the brakes , it was said that the brakes have been changed when the service was done , i went back immediately when i heard the noise its a very loud disturbing noise , they checked and poured water on the brakes and said it would stop , it didnt stop i went back and they said its dust ,it didnt stop i went back and they said im driving the car with my handbrake up which doesnt make sense coz the car would alert me that the handbrake is up and would i really always drive the car with the handbrake up ..NO ..I WENT BACK SPOKE TO THE MANAGER who made up all sorts of excuses as to why its making the noise ..with them trying to diagnose the car they never thought of changing the brakes again all they keep doing is giving excuses .. I have been to the branch 6 times with the same problem 6TIMES and the problem still persists and im not getting any help from Mercedes..i told them that they are mybe doing this coz my car is almost out of the service plan ..CAN SOMEONE PLEASE HELP ME THESE PEOPLE ARE NOT SERIOUS AND CLEARLY DONT CARE ABOUT THEIR BRAND