Click on the Alaunus app menu and find 'accounting'. Once there, click on the invoices tab and you will be redirected to the invoices page where a collection of all invoices for a set time period is stored(see "Invoices"). To edit an invoice, click on the desired invoice. This will redirect you to a page similar to the shown below where you can view, edit, send or download the selected invoice.
Once on this page, click edit at the top right corner of the screen and this will take you to the page below. Once there, make all necessary changes and click save. To discard changes, simply hit back and select 'leave without saving'. Once all changes have been saved, you will be redirected to the same invoice page, but with the updated changes.