26-07-2016 11:29 PM
I've opened up a case
By "case" I presume you mean a claim under ebay's money back guarantee? (i.e. not just a "change of mind" return request.)
If you were able to open a case it must have been within eBay's timeline, which is within 30 days after the actual (or latest estimated) delivery date. If it is still unresolved after 8 days you need to escalate it for eBay to step in.
I do hope that you used recorded delivery or similar, as when you escalate it eBay will require online tracking proof of delivery. It's a pity you didn't use eBay's MBG procedure from the outset, as they would even have provided a prepaid and tracked return label, which would have been charged to the seller.
For further information see eBay's money back guarantee:
http://pages.ebay.co.uk/ebay-money-back-guarantee/index.html