SKU & Style Item using FBDI with attachment-SKU item error "Attachment category does not exists"

While creating SKU and Style/Standard Item using FBDI with attachment - SKU item creation is failing with error "Attachment category does not exists" and the STYLE/STANDARD item gets created successfully.
On the other hand, When one or more than one SKU items are created using FBDI with attachment - items are created successfully.
Error is encountered only when a combination of Style/Standard and SKU item is created using FBDI having attachment.