air for the sits stop working on 2002 Mercedes-Benz CLK55 AMG

took the car to a mercedes dealer for the driver seat not working, when it came back the air for the cushions on the driver seat din't work. and now they want to charge extra. could you help me out. thank you, abe

What parts did they replace the first time? What are they telling you is needed now? Also, did they have to remove and refit the seat the 1st time?