Is there a confirmation button anywhere?

I have set up a recurring invoice. The invoice has sent to the client. I have emailed the confirmation to the client by going to the invoices section. However, in the recurring section, I can’t see any notification or anything different.

The client has paid the invoice and I have emailed the confirmation so how can I be safe that the system won’t sent the second reminder to him?

The app won’t send reminders for a paid invoice.