don't know how to remove it.
You can't remove it. Unless the seller agrees to cancel the sale you will have to wait until eBay places an unpaid item strike on your account, and then appeal it.
I imagine your appeal will probably be allowed. This must happen all the time, as eBay doesn't allow buyers to view motor vehicles until the listing has ended. (This is to prevent buyers and sellers arranging a private sale, evading payment of eBay's fees.)