To be honest I don't know how you could have been charged for 4 gift cards if you only had 2. To my knowledge each individual gift card can only be scanned one time during the transaction.
Call home office in Bentonville. Ask for market office direct phone number. Explain situation. They can give you a cash refund from your local stores office. It's called "customer sat" like satisfaction.
All that you need is your receipt. If their are 4 different barcodes then you have a problem. Nonetheless, not every transaction has to be debited back to your account. You can request cash. If one person is not accomadating then reach out to the one higher than him/her. Follow the chain of command until your issue is resolved.
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