A Winter Park college student thought she could turn an extra gift card into cash online, but a scammer wiped the card clean with a single phone call instead.

Chelsea Appel wanted cash instead of the $150 Target gift card she won at a party, and she thought selling it online could be easy.

"I thought I could do better on Craigslist, and I had friends who had good luck with it," said Appel.

On Craigslist, Appel had a quick offer from someone who said he was in Orlando ready to pay nearly $100. But first, the buyer wanted to confirm how much money was on the card by calling Target using a three-way phone call.

On a conference call, the buyer wanted her to punch in the card's account and access codes so Target's automation verified the balance without Chelsea giving him security codes.

"You don't have to say it out load, you can punch it in, and I thought that was a valid reason," said Appel.

That's what she did, but two hours later, the man never showed up to buy the card and when she called Target to check it, she heard, "The balance was zero dollars."

Security experts said scammers can record the phone tones, then turn them into card access codes so they can shop online or transfer the balance.

The seller scam is the latest gift card threat.  According to the Better Business Bureau, buyers remain the biggest target who think they're getting a deal from online sellers.

"The card you receive could already be expired.  It may already have been spent. It may be a fraudulent card," said BBB Vice President Holly Salmons.

Many scammers use electronic readers to steal access codes before the cards are sold, then transfer funds once the cards are loaded with money.

Appel said she won't be selling any more gift cards online.

Target told Action 9 it takes the security risks seriously, but since Appel’s incident didn’t involve the company directly, Appel will need to file a police report.

There are reputable companies that help consumers re-sell gift cards online, like Plastic Jungle, but those sites charge fees.