When you messaged the seller what was their reply? Did they send you tracking to show delivery? If they did, and you checked this on Yodel's website, you will not receive any refund from eBay, but could try your payment provider, or approach Yodel see if you can get a reply, as to where they left the item.
Or, just open a case for item not received. If there's a valid tracking number, when entered, it will close the case straight away. If not, no valid tracking provided, no refund, escalate the case on day 4, eBay step in and force the refund.
@kib8960
