Issue your first invoice
Open Finance and create an invoice for a real customer — even a small one.
Share the secure public link over WhatsApp. That is the default sharing path.
On paid plans you can show a DuitNow panel. Free focuses on tracking whether it was paid.
When money arrives, mark the invoice paid so the ledger stays honest.
Invoices that live only in WhatsApp are the problem Free is for. See plans and pricing and the modules behind the invoice.