Error Code 10028
Item location cannot be revised if the item has bid or active Best Offers or is ending in 12 hours.
Listing is either an auction with less than 12 hours left or a fixed listing with the Best Offer option enabled.
If the listing is an auction, eBay will not allow changes to the listing if there is less than 12 hours left before bidding finishes.
If the listing is a fixed price item, you have a pending offer from a customer which needs to be addressed before you can make changes to the listing. Log into your eBay account and respond to the offer, then try revising again.