What Do I Do If I Have More Than One Of An Item?
Once an item is added into the 'Ticket' section you can press the number on the left of the item name, this will load a box which gives you the choice to enter multiples of the product:
How Do I Modify Only One Item?
If you add a multiple quantity onto the POS and then need to modify/add a note to just one of them, you can simply ungroup the item. To do this you will need to swipe on the product which will load a new menu and select 'Ungroup', this will then seperate the multiples of the item as can be seen below: