The seller is not allowed to change the shipping address after the purchase and retain eBay's Seller Protections, though some choose to do it anyways if requested. The proper thing to do is to request to cancel the purchase, and then reorder with your correct address at checkout. The seller will still need to respond and approve the cancellation request, depending on whether or not they have already shipped the item.
I strongly recommend you update all of the addresses shown on this page to avoid this problem in the future: https://accountsettings.ebay.com/uas/addresses
Volunteer Community Mentor | Posting ID
