You can see several statuses in your affiliate dashboard’s “status” column. Here is what they mean:

Pending means that the commission is confirmed by us but is not yet paid to you. Once we pay you this commission, it will turn to “paid”.
Paid means that we have already paid you this commission.
Not Confirmed means that a referred user has initiated a purchase, but their purchase has not gone through due to a problem with their payment.
Refunded means that the referred user has received a full refund within the allowed refund window.

The last two cases mean that you’ll not receive a commission for these orders.