Some orders can no longer be refunded due to the inability to issue the refund. This can happen for a few reasons:
The merchant processors used by the company to process and refund cards has changed (ie from WorldPay or OpenEdge to Stripe), or
The credit card is replaced or fraudulent, or
The refund period has expired by the card processor.
If this occurs you will need to ask management to issue a refund by check or credit note to the customer. Please note the order number, and take the customers phone number so they can be contacted.