I wouldnt worry mate, i have been through this and the buyer always wins.
i’d advise you to open communications with ebay, they will have copies of all correspondence if you have gone via ebay.
we sold a pram few years ago it was in very good condition, the buyer changed her mind when she saw it and wanted her money back.
i fought it via ebay and opened a complaint, she won in the end, ebay paid her back then came to me for the money.
Different story though possibly if they would have taken it and then said they didn’t want it because it was dmamaged. How do you prove it was damaged when collected rather than damaged after it was taken? Tricky one that