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This happens when the Inventory Item is already loaded to BUZ this includes any deactivated Inventory items and has a PKID, these Items will need to be removed from the list.
Check your import file to see if you have the same Material, Material Type and Colour, to see if BUZ is trying to create the same Inventory Code as an existing one in the system.
Inventory Item Code can't be generated by BUZ
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