MIAMI (CBSMiami) – Americans say they lost nearly one and a half billion dollars to fraud last year. Now, a quickly growing phone scam is targeting banking customers via text message.

Everything seemed legitimate when Pieter Gunst answered a call earlier this month that appeared to come from his bank.

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The caller asked Gunst, who lives in California, if he’d attempted a withdrawal in Miami. After Gunst said “no,” she asked for his bank member identification and he gave it to her.

“And at that point the lady said, ‘OK, we’re going to send you a one-time verification pin so we can check your identity,’” Gunst explained.

The scammer used Gunst’s ID to prompt a text message from the bank’s real phone number, like others he’d received before, with that verification code. He read it back over the phone, which allowed the caller to access his account and list off actual bank transactions.

“The fact that they used the bank’s own infrastructure to send that code to me, which then allowed them to reset my password, made it very credible,” he said.

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It was only when the caller asked Gunst for his bank pin number that he realized something was wrong, hung up, and called the bank’s real fraud line to lock his account.

“A lot of scams come in through the phone, and more and more we see them coming in through text message,” said Katherine Hutt with the Better Business Bureau

Hutt says some red flags include if any caller asks for your name, address, social security number or account numbers. And the best way to make sure you’re really talking to your bank? Just call the number on your card.

“Whether it’s a small local community bank or credit union or one of the biggest banks in the country, they can be impostored, so you just have to be really careful,” Hutt said.

Gunst, who’s a technology lawyer, later tweeted about the scam. He told CBS News that several people responded to him with similar stories.

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The Better Business Bureau says it’s a best practice to regularly monitor your bank statements for potentially fraudulent charges.