Sold an oven, buyer said it arrived broken

Hey all, I shipped out a big oven on eBay using their ups label and when I had shipped it, it was perfectly intact. Buyer opened a return request requesting for refund since it was damaged and sent multiple pics of the damage. It seems ups mishandled it. The problem is, I sold my store hence why I sold that oven. I have no use for it especially after it arrived there broken. I talked to eBay and they said file claim with ups which I did and ups has the standard $100 insurance only (I did try to look to add insurance on the eBay ups label but couldn’t find it) my item was nearly $1500. Any advice?