I have the field “_pip_invoice_number” in database in wp_XXX_postmeta. I need this value most urgent in order-export csv-file. So I fill this into the frame “custom order fields” but export isn’t working – no including of this value “_pip_invoice_number”. How can I export this very important value into the order-export csv-file?
Image how I fill this in:
http://shop.pronatur24.eu/wp-content/uploads/2013/08/custom_order_field.jpg
