Double Billed

Ever been double billed? I have been. I just got a bill from my podiatrist for some work that I already paid for early last month. Just got this very same bill a few days ago with a note attached saying that I am late paying this bill. I have never been later paying them, ever. What I am going to have to do(Ok well, I don't know that I HAVE to) but I am responding to their bill with a copy of their bill and a not that says I have already paid it and a copy of my cancelled check. I realize that folks do make mistakes. Still, it is a little bit aggravating , though. Ever had this happen to you? How did you handle it? Thanks for letting me vent a lil bit:)