The option to automatically apply credit notes on customer invoices is only exclusive to some regions in QuickBooks Online (QBO), Domeau.
In the QBO ZA version, the ability to automatically apply credit notes to your customers' invoices is currently unavailable. Hence, you can't see an option to use this feature within your account.
As a workaround, you have to manually apply these credit notes directly to your customers' invoices you want to take effect in the transaction.
Moreover, here's an article you can check if you want to generate a report that'll suit your business needs:: Run a report.
Feel free to revisit this thread if you have further questions or inquiries with regard to your customer credit notes. We're always here to help.
