I had something similar happen to me a couple weeks ago.
I just started selling on ebay and I was selling a bath fan. When I was originally filling out the listing i skipped right past that section where you can block certain countries from bidding. I just assumed that nobody was dumb enough to buy a $30 bath fan that weighs 11lbs and pay to have it shipped overseas..... silly me.
Sure as heck ... within a couple hours of listing someone from some conglomeration of islands somewhere on earth (I dont remember where they were from but it wasn't Kansas) messages me and asks how much it costs to have it shipped to them. I tell them that I don't ship overseas on items like this.
They kindly thanked me for my time and then bid on it anyways.
Luckily they got overbid and didnt win the auction ..... but I learned my lesson and now I TRIPLE CHECK that I have those boxes checked on items that I won't ship overseas.