Once the invoice is visible, click on the Edit button
You can make below listed changes on the invoice -
1. PO Number – Click on the PO Number box and automatically the PO number box will appear on the invoice (just before hours), put the PO number and click on save invoice.
2. VAT – You can add VAT to the invoice by selecting the VAT percentage from the drop down in VAT tab and click on save invoice.
3. Footer note – You can amend the footer note on the invoice by entering the details you would like to add on the invoice and click on save.