You only get one opportunity to open a return case through Ebay.
All you can do in this situation is contact Ebay Customer Services.
Explain what happened, as you have done here, and ask them if they could possibly open a return case for you.
They may refuse but it is worth a shot.
Use the link to get a callback.
https://www.ebay.co.uk/help/eua?id=5275&mkevt=1&mkpid
"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)