It makes sense to allow barcodes to be identifiers in import as it is the only thing that is the same for everyone. To work around this I have used barcode as item_code. But still, somehow it can’t find items even this way.
I mean in the database item_code is let’s say 4560842037320 and in the update file, item_code is also 4560842037320. How is it possible that the item is not found then?