In order to modify a line item in an invoice, you'll first need to locate the invoice in question. To access a user's invoice from the user page:
Select Users from the left-hand menu (then Teams if you are looking for a team)
Locate and click on the user or team
Scroll down and select the 'Invoices' section on the right side panel
Click View on the invoice that you'd like to edit
Note: You can also locate any invoices from the Invoices page in the dashboard.
Once in the invoice, to modify a line item, hover over the line item and click into it. Here, you'll be able to modify the charge (either changing the quantity or the unit price), the tax amount, or the description for the line item. To save new changes, click Add credit in the bottom right.
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