Red Flags Checklist

We receive several alerts each day from our fraud dept on customers who have had unusual or suspicious activity on their debit cards. If the automated system can't get in touch with the cardholer by phone, an alert is sent to the bank so that someone here can try to contact the customer. According to the new Red Flag rules, I understand that we have to at least attempt to contact each cardholder that we have received the alert on. In some cases, the fraud dept has already placed a temporary block on the card if warranted and in other cases, the card is left active. I wonder if it is necessary to try to contact every alert customer or just the ones that the temporary block has been placed. What is everyone else doing?

Our bank has a system that automatically contacts all phone numbers on file several times. If it cannot reach the customer, it will block the card. Either way, we get a report telling what happened & we try to contact the customer if he hasn't already been spoken to.
I would contact all customers. It's better than a bunch of Reg E disputes.