Give me a few tips on what to do about my Nikon D3100?

I know this is a long shot but could someone help me Please. I brought my camera in May 2011 and have been doing good but we noticed early on my flash doesn't work and it has been that way since the day we brought it. It was finally sent back to Nikon (after our big events for the year were done) to be fixed last month and I just got it back yesterday and it was not fixed so after talking to a rep at Nikon yesterday he gave me a few tips to get it working just to get me through Christmas and New Years… Well I'm lost cause it not doing anything now… Please Help… I wasn't ready to venture into A and S modes yet but I know I will have to… Thanks

Added (1). I Just called Nikon again for more trouble shooting and still nothing after playing and resetting the camera to A, S AND P modes

Added (2). I will send it back to Nikon because it is still under warranty, but I will need to wait until after Christmas because I need to take pictures of my children for christmas and it will not get back to me before Christmas.

Send it back to Nikon as it is under warranty and get it fixed… Make a complaint…