I had the code legitimately. ebay help just confirmed;
“
We are aware that there was an issue with the voucher that prevented it from being applied and we are currently investigating this. We will be looking into a way to ensure that members like you still get the benefit from the voucher.
For the meantime, you can make payment in full and we will reimburse your PayPal account with the discount amount for the completed transactions. Please note that it will take up to 14 days to see this reimbursement in your PayPal account.”
You just have to open a dialogue with them, detailing the items you purchased and a few other details.
I suspect if you werent on the list to get the code originally, you’re at the mercy of ebay. better hope their PR face wins over their accountants.