You can check on your users' pending invoices within your Optix dashboard. Individual pending invoices are accessible via the 'Users details' tab from Users page. If the pending invoice is not visible, try clearing the status bar at the top of the invoices page below.

You can also access this invoice from the Invoice items tab, located under the Invoices page of the web dashboard. Once a Pending Invoice is due, it will automatically move to the Invoice page and be converted into a Due Invoice.