Adjusting Tax Amount 
You can manually adjust tax amounts per vendor or customer requests.
Note
For sales A/R documents, you can apply the tax amount adjustment only for China, Japan, and Korea.
For a specific document, choose , and select the Visible and Active boxes to activate them.
On the Contents tab of the document window, adjust Tax Amount (LC).
From the SAP Business One Main Menu, choose .
Select the Manage Freight in Documents box for each purchase/sales document type from the Per Document tab.
For a specific document, choose , and select the Visible and Active boxes of the freight taxes.
On the Contents tab of the document window, adjust the freight taxes.