Once you've approved (non-integrated companies) or published (integrated companies) an invoice, the fields won't be editable and will show as greyed-out.
If you need to edit the invoice after validation, you can unapprove or unpublish it.
This can be necessary if you've assigned incorrect nominal categories.
From the invoice details
You can access an extracted invoice from the Inbox or Activity tabs.
Click the invoice number or file name to access its details.
Click the un-publish or un-approve button.
From the Inbox or Archive
You can un-approve or un-publish one or several invoices from the Inbox or Archive tabs.
Access the Inbox or Archive tab.
Locate the invoice.
From the Actions button on the right, click Unapprove or Unpublish.
Once unapproved or unpublished, the dropdown menus and text fields are editable again.
📌TIP: Tick the box to the left to select multiple invoices, then select the Actions button at the top of the list.
📎NOTE: Marking an invoice as unpublished doesn't delete it from your accounting software. If you're republishing the invoice to your accounting software, you must delete the first instance of it manually from the software.