The current form for order fulfilment only allows for manual accept, reject, ship lines. This can result in errors in the picking process as there is no validation that the POS user is picking and packing the correct item. It also could result in lines from mixed orders going into the same parcel accidentally.

Suggestion is that the user can scan an item into each stage. A rework of the form would be required to handle an order at a time, as this is how a store would action the orders.

The form should behave similarly to the inbound and outbound operations where you select the order header and then build the lines that are being picked, packed, shipped

In store most retailers would handle an order at at a time, not an order line at a time, so having the initial form at a header view would be beneficial. The user can then either scan or manually select (as is process) at each stage.