When the seller asked you to close the case, did you close it? If you did, nobody at ebay will help you. The case is closed. Also, I think you have 30 days from the expected delivery date to file a claim. I am guessing it is too late for that too.
The only way that will get your money back is to contact the credit card company you used to pay for the purchase. Call them first. They usually issue a credit to your account immediately. They do the investigation about your claim. If they need additional information, they will contact you. For the seller to prove that you received your order, they have to provide a tracking number showing that it was delivered. I presume, no such tracking number exists.
So stop communicating with the seller and ebay, just call your credit card company. Before you call them, have the information they may need from you ready. E.g. date of purchase, the exact amount, potentially they may ask for the sender's address, an ebay order number, although I don't think that they will need all that when you call them.
