eBay Error 10048: The shipping and handling costs cannot be changed if an auction-style listing has a bid or ends within 12 hours, or a fixed price listing has a pending Best Offer.

Why this happens

The shipping cost was changed, but eBay temporarily blocked this action to protect buyers who are actively engaged in purchasing your item (or to prevent changes from occurring immediately before the listing ends). Why eBay enforces this: Postage costs are part of the total price buyers commit to. eBay stops shipping cost changes while bids or offers are pending so buyers are not charged differently from what they saw. When it usually happens: It usually follows a carrier price increase, when sellers raise shipping costs on all listings at once.

How to fix it

This error in other languages

German: Die Versandkosten können nicht geändert werden, wenn für eine Auktion Gebote vorliegen oder sie innerhalb von 12 Stunden endet oder für ein Festpreisangebot ein ausstehender Preisvorschlag vorliegt. French: Les frais de livraison ne peuvent pas être modifiés si une annonce au format Enchères a reçu une enchère ou se termine dans les 12 heures, ou si une annonce à Prix fixe a une offre en attente. Italian: Le spese di spedizione non possono essere modificate se un'inserzione in formato Asta online ha ricevuto un'offerta o scade entro 12 ore, oppure se un'inserzione Compralo Subito ha una Proposta d'acquisto in sospeso. Spanish: Los gastos de envío no se pueden cambiar si un anuncio de subasta tiene una puja o finaliza en las próximas 12 horas, ni si un anuncio de precio fijo tiene una Mejor oferta pendiente.