Hello,
I have gone through the listing you mention. It mentions 30 days warranty. You have purchased the same in August. Which means the product is no longer covered under warranty.
I have also noted that you have rated the same seller twice, which means you have made repeat purchases from him.
I also see that the seller does not have any listings on the site which may mean he is no longer a seller on the site which may be the reason you have not received any response to your emails. You would be advised to have the product repaired locally.
I also see the pathetic standard response of the eBay team without going into the actual complaint. No buyer entitled for any purchase protection 90 days after the auction has ended which it unfortunately had at the time you posted this.
Regarding finding contact information of the seller, Sapana has given you the correct procedure.