How to return/ refund when purchased as a guest?

[ricveth0]

purchased as a guest. Seller sent wrong item. Unable to start return refund process. 
website puts me in a loop because they can’t find my order history. Of course. I bought as a guest. 
this was my first eBay purchase. Likely my last if I can’t get a refund. Any help ?

[disneyshopper]

Purchases made as a guest are separate from purchases made as a registered member. You will need to sign in with the email address you used as a guest along with the PASSCODE that ebay sent to you in an email. Then you can file a Returns Request.