An Amazon employee works to fulfill same-day orders during Cyber Monday, one of the company's busiest days, at an Amazon fulfillment center in Orlando, Florida, on Dec. 2, 2024.Miguel J. Rodriguez Carrillo | Getty ImagesAmazon is adding a 3.5% "fuel and logistics-related surcharge" to fees it collects from third-party sellers who use its fulfillment services, as the war in Iran stretches into its fifth week, driving up oil prices.The surcharge will take effect on April 17, for sellers in the U.S...