I am happy for buyers to return items, unworn, unwashed and in the condition they were set in, for a refund of item cost only. I also offer then the option of using my photos and description if they would rather resell it. If the fault is mine then I refund in full.

With this one as long as you are sure it was as described if they have or are going to open a Paypal dispute make sure you put your case very clearly, state that it was new in and had never been worn or washed and that any colour difference must have been down to the buyer's monitor as the photos look correct on your screen.

Paypal should find in your favour but rumour has it that is decided by the toss of a coin so don't be surprised if they find against you.