Problem with a buyer

Hi All,

I sold a dress, was worn 4 times - and immaculate. I bubble wrapped an packed. The buyer received it and is requesting a refund as states the dress has a pull in it which it did not. The buyer buys expensive dressers (like mine) at a cheap price, and clearly onsells them. It appears to me that she did not like the dress and now is saying their is a fault, and would like a refund.. however, it was perfect when it left. I doubt Australia Post would have damaged it, as it was bubble wrapped.. I dont want to get into a tiff with a buyer, but I dont want to risk my 100% feedback over a sale of $36! Can anyone recommend what to do?