The first step you have to do before picking each picking request is to assign a staff.
If your role is As a warehouse manager that have who has to manage the picking process, you can see all the picking requests (staffs can only see picking requests assigned to them) and assign picking requests to the staff in your warehouse.
After you have selected some picking requests, you can click on Assign staff button.
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Therefore, the Select Staff to Assign popup will show for you to select which staff to assign.
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You select a staff here then clicking on Confirm button to finish assigning staff to the selected picking requests.
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After you have assigned successfully, there will be a message show as above.
Failed case
Please note that there will be some cases that you cannot assign/reassign the staff for the picking requests:
The selected picking request is in “Picking” status (You cannot change picker for picking request that is being picked).
The selected picking request has been assigned to a batch (Because the picker of that picking request will follow the picker of the batch, so you must change the picker of the batch).
The selected pickers has been deleted/disabled or unassigned from source.