Credit can be deallocated by double clicking in the "Deallocate" column, and typing in the amount that should be removed from the bill item. Select the [Account] button to submit the changes.
The Info column of the journal will also display potential issues with bills. Any items that have been flagged will be highlighted in blue.
The Missing credit message will be shown for part-paid bills. Once the bill has been fully paid this message will disappear.