Go to Kitchen Settings > Stock Management Justifications (/admin/movementsreasons; shown when the retail or wholesale module is on). The list has Active and Inactive tabs with ID and Description. Click Add new or an existing row to open the New/Edit Stock Management Justification form with Description (max 100 characters) and a Status switch, then save. Active reasons appear in the Reason of movement drop-down of the Edit Stock windows (admin and wholesaler portal). The reasons used automatically by the system - Sold for orders and CSV deductions and Void for upload reversals - are built in and should be kept active.