Select Authorise from the side menu.
This will show a list of all invoices ready for authorisation.
Use the pencil icon to review an invoice.
Fields with a pencil icon next to them can be edited if necessary.
Use the Approve and Deny buttons to update the authorisation status on the invoice.
When an invoice is denied, you will be asked to give a reason for the denial, and can add any notes.
It will then be returned back to the originator (at draft level).
Approved invoices will move onto the Ready for Payment level.