poor service

I purchased foundation from the store with the help of the make up artist there. It turned out to be the wrong colour but would not have realised it because when she was trying it on my face she put on such a small amount on my face. When I used the make up the next day using much more than the make up artist the previous day the foundation turned out to be two shades darker than my skin. I went to the store to complain and the girl I found there said that there was nothing that she could do because I had already opened the product. She then said that i should write my details on a piece of paper and she would get the manager to call me the next day as she wasn't at work on that day it is now 5 days later and I still havnt recieved a phone call from the manager this was such bad service!!