I've sold an item on eBay and the buyer has opened a case against me saying it's a different size to what was listed. I think I panicked a bit as it's the first time this has happened so I told her to return it and I would refund her. However now I've had time to think I'm convinced it is the size I stated. If she sends it back and the size isn't wrong what can I do? I didn't take any photos of the size label but I have learned my lesson now!