OP, did you upload the tracking number in the dispute?

If you didn’t do so, then eBay’s automated process would not know that the items were returned.

You could contact eBay Live Chat with the tracking information and request an appeal based on that new information.

If that is unsuccessful, you can contact your bank and ask for a chargeback. However, do not do this unless you’ve exhausted the eBay avenue because eBay will immediately close an eBay case or appeal if simultaneously a chargeback request is opened. Use this as your last resort.