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Authorities are raising the alarm about gift card draining scams. The Federal Trade Commission (FTC), Department of Justice (DOJ) and multiple state officials have issued warnings this season about gift card draining scams.

Shoppers who purchased gift cards at Walmart, Target, or other major retailers are being told the cards have zero balances on them.

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Authorities say scammers switch out the bar code on the back of the card with a fake bar code. When the gift card is scanned and paid for at the register, the money that was loaded on the card is sent to a bank account that the scammer controls.

“I was really shocked by it,” Suzanne Gdovic, a victim of the scam, said Monday on “Fox & Friends First.”

Gdovic says she loaded $200 on a gift card at Target for a friend whose daughter was having a baby.

“I gave it to her. She went to Target to try to use it, and she was at the cash register checking out, and she was told there was a zero balance on the card and was also told that the gift card was assigned to another person’s account. There was no money there for her to use for all of the things that she was buying for the new baby,” she continued.

“My particular gift card, the back of it was exposed, so it was very easy for them to access the information off the back of the card. There was a silver lining on there. That protective security code had been scratched off, numbers were taken when they took that gift card out of the store. Then they expertly [put] back on that silver lining,” she said.

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Other victims shared similar stories about drained gift cards purchased at retailers like Walmart and CVS.

A Houston woman lost $800 when she purchased a gift card at Walmart.

Susan Kunz purchased $1,000 worth of gift cards that she planned to give to several families in need at her church.

But when she checked to confirm the balance on each card. She was shocked to learn that one of the cards had already been drained.

“The cards had been only in my possession so the questions was ‘How does this happen?'” Kunz told KPRC. “And if this is happening to us, who else has this happened to?”

“If we had not gotten this figured out we would’ve been handing out cards to our families,” Kunz said. “They would’ve been filling up their baskets with toys and food. They would’ve gotten to the cash register and cards that had been given to them by a church would be empty and that is a terrible thing.”

After Walmart failed to refund her money, Kunz filed a police report.

“We need our money back,” Kunz said. “We’re going to come up with something different for our families. We’ll be giving money to our families this Sunday. Obviously, we will not be giving them Walmart cards.”