Update invoices.adoc

modules/savanna/modules/administration/pages/billing/invoices.adoc

@@ -12,17 +12,41 @@ image::billing-nav.png[width=300]
 
 . Select the btn:[Invoices] tab to view the invoices list.
 +
-image::invoice-list.png[]
+image::invoice_tab_.png[]
 +
 .Here you can view general information on invoices, such as:
 * *Invoice Date*: The date the invoice was issued.
 * *Invoice Status*: The status of the invoice.
 * *Invoice Period*: The period that the invoice was issued in.
-* *Total (Credits)*: Total credits used during that invoice period.
 * *Total*: Total charge during that invoiced period.
 
 . To export a specific invoice as a `.pdf` select the btn:[PDF] button under btn:[Export As].
 
+== Invoice status
+Each invoice status indicates the stage of an invoice in the billing lifecycle.
+
+=== In Billing Period
+
+The invoice period is ongoing and charges are still accumulating.
+
+image::billing period.png[]
+
+=== In Grace Period
+The billing period has ended, but the system will automatically attempt payment after the grace period.
+
+image::grace period.png[]
+
+=== Processing
+Invoice amount is being finalized and is not ready for payment.
+
+image::processing.png[]
+
+=== No Payment Needed
+The invoice does not require payment (e.g., zero amount or covered by credits).
+
+image::no payment needed.png[]
+
+
 == Next Steps
 
 Next, learn about other billing topics on the xref:savanna:administration:billing/index.adoc[] page or check out the xref:resources:index.adoc[] section.