I bought an item on ebay that does not fit my device so I immediately wanted to return it, I opened a return and the next day the seller closed the return and stopped contacting me, I don't know how to report it to ebay
If you used "Doesn't fit" as the reason that's classed as "change of mind" which private sellers do not have to accept. For future reference, if it's the seller's fault use "not as described". There's nothing you can do via ebay now the case is closed but contact your payment provider and see if they can help with a refund.