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Why am I receiving the Error with RelistItem call?
<ShortMessage>BySku Support Required</ShortMessage>
<LongMessage>Requires SKU support operations when trying to revise or relist an item that was already managed by the SKU.</LongMessage>
You receive this error when ItemID specified in your RelistItem request was orginally listed via AddFixedPriceItem API with InventoryTrackingMethod set to SKU. In this case, you will need to use the RelistFixedPriceItem call instead :
| <RelistFixedPriceItemRequest xmlns="urn:ebay:apis:eBLBaseComponents">|
By specifying ItemID but SKU in RelistFixedPriceItem call for the listings that originally listed with tracking inventory by SKU will drop the InventoryTrackingMethod SKU tag ( <InventoryTrackingMethod>SKU</InventoryTrackingMethod > and indicate that you perfer to track your newly relisted eBay items by eBay Item ID.