Not 100% sure I have understood your question, but if a seller is not being helpful for a return, for item not as described, then open a case for this in the Resolution Centre.
https://resolutioncentre.ebay.co.uk
Escalate on day 4 if not refunded beforehand. Do not close the case early for any reason, and do not forget to escalate.
If this is a return for change of mind / does not fit reason, and the seller has a No Returns policy on their listing, they can refuse your return.
