To manage pre order, follow the steps given below. 

1. Navigate to Inventory

The Inventory page will be displayed. 

2. Navigate to Pending section.  

3. Tap Pre Order. 

The Purchasing dialog will be displayed.

4. Enter the quantity in the Quantity text entry box.  

5. Enter the comments if any, in the Comment text entry box.  

6. Tap Save

The pre order details will be added.