10-01-2021 12:33 PM
Returns for faulty, damaged, and not-as-described items are at the seller's expense. So it seems that you went down the DIY route instead of using Ebay's returns system as you should have done. So that you know what to do in future, read Ebay's Money Back Guarantee. It's on every listing, in various other places across the site, and on your order confirmation.
You haven't provided any dates. If you're within 30 days of the delivery estimate on the order, and have tracking to prove delivery, open an Ebay Not-as-described case (not a return request as you have nothing to return), and enter the tracking number into it. Once it shows delivery or attempted delivery back to the seller's Ebay-registered address, the whole of your original payment will be refunded.
If you're out of time to open an Ebay case, and have tracking to prove delivery, open one in PayPal if that's how you paid, or with your card provider.
Ebay, PayPal, or any payment processor, can't help you get the return cost back. If the seller won't refund it voluntarily, and is in the UK, go to the CAB's website to learn what to do via the legal route.
The time to check feedback is before you buy, not afterwards. That's what it's there for.
Last but not least, you only shipped the bike back on Friday, you say. Most carriers don't work at weekends, and the seller is unlikely to receive it back for at least a week under current circumstances, so do bear that in mind.