If you have added an item and it is not showing on POS then probably you haven't enabled it to be displayed on POS. But fret not, it is very easy to do! 

Steps:

1. Click on Inventory >> Manage Inventory >> Products,

2. Select an item by clicking on its Item ID or click on the Edit icon.

3. Under the Quick Settings tab, you will find a checkbox Display On Point of Sale. Enable it to display an item on the POS screen.

 

4. To hide an item from the POS screen, just unmark this checkbox.

5. You can also enable or disable "Display On Point of Sale" for multiple items from the listing page.