I have a problem with my orders on zen-cart that are paid via paypal.

My orders that are paid by check/moneyorder are fine. But if they choose to pay via paypal, they make their payment in paypal. We get their money, however the order does not appear in zen-cart. Their customer information does, it is just the order that does not.

I have checked port 80 with my hosting company which is godaddy, but what else should I do?