Are they perhaps asking to clarify some detail ? Perhaps the label they've printed is not showing a postcode clearly.
Can't see how this is a scam, for once you purchase and pay for an item an address is visible to the seller, something is not clear, so they are wishing to clarify.
Send them a polite message if you wish, asking if there's something not clear with the address eBay have provided.
@rembpic0
