Header Billing Plan net value is 0

Hello All,

I have created 3 line items and i am doing billing plan at header level .

Item 1 = 10

item 2 = 20

item 3 = 30

Net value = 60

Now the issue is i dont want to run billing plan line by line . i want to do it at header level (Milestone billing). I have assigned milestone at header level as well. When i click on header then select billing plan i get net value = 0

I am doing Ek02 for each line item and profit margin at header level. How to solve this issue