Points are added to your account once you make a purchase.
If you return an item and are issued a refund in the original form of payment, the points awarded for that purchase will be deducted from your account balance.
If you return an item and receive a refund in the form of store credit, the points you earned for that purchase will not be deducted from your account.
If you return an item for which you used rewards points to purchase, you will be refunded the dollar amount of your purchase, and points used will not be re-issued to your account.