I went to process an invoice for a purchase order that was received in AP-C, but when I looked for the item received it is not there to be picked.  Under IN-A, it shows that the item was received, but is still open-not yet applied to an invoice?  There are other items available for picking that were received at the same time the missing item was picked for the same purchase order. Do you know what may have happened, or how to fix?