Dry Cleaners Messed up... What should i do?

I recently Purchased a spring coat from Banana Republic. The coat had ons on them and inside the ons were white decrotive pieces. I had it dry cleaned because the coat was pretty expensive and should not be washed in the washer and dryer. When i took it home and saw the job they did, i noticed the ons were now empty and the white pieces inside each on were gone, except for 2 or 3 of them. The coat is ruined without these as it looks tacky. I do not know what i should do, is the cleaners liable for the coat? Can they repay me to get the coat fixed or repaired? or is it my risk brining it there so i suffer the concecouncious?