Open the 
Purchase Order
window. and browse to the order that you entered the item charge
on.
Click Line and select Item Charge Assignment. The Item Charge Assignment (Purch) window opens.
In this window, the lines are already filled in with the lines from the open order.
Add lines from other documents if the charge relates to other lines. If you click Functions, you have the choice between getting receipt lines, getting transfer receipt lines and getting return shipment lines.
Note that if you are assigning the charge from a separate invoice, you must fill in the window using one of the abovementioned functions.
You are now ready to assign the charge. You can have the program suggest an assignment for you first and then adapt the suggestion to your needs.
Note that if you do not want to assign cost to a line, you can skip step 4 for that assignment line.
In the Qty. to Assign field in the first assignment line that you want to assign this item charge to, enter the relevant number of item charge units. You can enter decimal numbers in this field, for example if you entered the number 1 in the Quantity field on the order. You can also enter a formula.
Note that at the bottom of the Item Charge Assignment (Purch) window, status fields show you how much you can assign, how much of this you have already assigned, and how much is left to assign by both quantity and amount.
Exit the window by pressing Esc.