Hi,
The customer likely didn't redirect back to your site and the Storefront didn't receive the confirmation from PayPal that the payment is made. Please make sure to follow the instructions to set up PayPal Standard in the Users manual?
"Checkout using PayPal Website Payments Standard relies on the Web browser redirection to a PayPal hosted payment page and therefore, you need to configure the return URL to ensure the customer is safely redirected back to your site after completing their payment on PayPal. To configure the return URL, login to PayPal Web site and go to
Profile. Then go to
Website payment preferences. Enable
Auto Return and set the
Return URL field to your Web site’s address (e.g.
http://www.example.com)."