Not able to generate Pick Slip after Pick Wave Generation

Summary:

We are testing Back-to-Back Sales Order (Make) flow for a Customer Demo and are stuck at Picking Step. After generating and releasing the pick wave for the sales order, the system is not generation any Pick Slip. It shows the following message after pick wave generation:

"Pick wave XXXXX was released. Number of pick slips: 0 and number of picks: 0.

Number of Shipment Lines Selected for Processing: 0

Number of shipment lines for which the item was substituted: 0.

Number of shipment lines canceled: 0.

Number of shipment lines backordered: 0.

Number of shipment lines released to warehouse: 0.

Number of shipment lines staged: 0.

Number of shipment lines shipped: 0."