I think this is odd too! I contacted coach about the issue a few months ago but they just pretended there wasn't an issue. I was a bit disappointed and it put me off buying one quite a bit!
I actually talked to a CS rep on the phone today and she said best thing to do would be to take the bag into one of their stores and send it in for repair. And since it's obviously a design defect, repair department would address best way for me to deal with it.