Our PayPal integration uses a feature called IPN, or Instant Payment Notifications to automatically record payments and refunds on Invoiced. The only insight we have into PayPal's payment network comes from these notifications. Until we receive a notification that a payment has been made or that a refund has been issued we cannot otherwise know when these events happen due to the nature of PayPal.
Usually notifications from PayPal are near instant, however, there have been cases where PayPal takes several hours to deliver notifications. If a payment or refund has not been recorded in the dashboard within a few hours then please feel free to contact us about it.