There is nothing you can do through Ebay.
Use google to investigate the seller - do they have a presence outside of Ebay? If you can find a phone number or address, contact the seller.
If you have any paperwork such as a receipt, you may be able to get some help or advice from the maker.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)