Now criminals are widening their net, targeting customers of other banks as well, tricking them into sending them money through Zelle.
And banks mostly say it's the victims' responsibility.
Among the latest - a longtime Chase bank customer, who told his story to KGO-TV.
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This viewer wanted to expose what's going on - after he got bilked by imposters claiming to be from Chase bank. Just like they did with Bank of America customers, these crooks say they're helping you stop a fraud when really, they're the ones stealing your money.
"I was like holy smokes! No way! This is happening to so many people!" said Page Pollak of San Francisco when she learned more about the scam.
"This person told me someone was trying to scam me," Claudia Rivera of San Jose.
RELATED: Banks tell customers they're responsible if they pay Zelle scammers
"It appeared as if it was a text message from Bank of America asking if I was trying to transfer $3,500," said Katie Singer of Oakland.
"I said 'No,' and within 15 seconds my phone rang," said Donna Stoker of Cartersville, Georgia.
"He said we're gonna get the $3,500 back," said Pollak.
"'You're gonna go to Zelle and you're gonna send it to yourself,'" Rivera says she was told.
RELATED: More victims of Bank of America, Zelle scams come forward; here's how to protect yourself
They all were targets of the same scam. All believing they were reversing a fraudulent transaction. All were actually sending money straight to the imposters.
"$3,500 was gone right then and there," said Pollak.
"It was a real eye opener," said Rivera, crying.
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And all were customers of Bank of America. Until now.
It was a Friday night when Donald James of Lafayette got the frightening text: "It says Chase Bank, fraud alert, Zelle payments in the amount of $2,000," James told said. "Chase Bank... if you made this transaction reply yes."
"'If not, reply, no.' I said, 'No.' And my phone rang. And it was Brian from the Chase bank fraud department," he continued.
Or at least he thought it was the Chase Bank fraud department.
"The caller ID number was identical to the one on the back of my Chase card," he said.
But the caller ID was fake.
"And he goes, 'Let's go over these charges... did you send a Zelle for $2,000?' I'm like, 'No,' and he says, 'We need to send the money back to yourself,'" James explained.
The imposter told him to transfer the money with Zelle using his own phone number. It seemed like it was going back to James.
"So I was getting notifications on my phone that I had sent myself money," James said.
He typed in the transaction codes... and the imposters snatched the money at the other end.
"To the tune of $7,000 over several transactions," he said.
When one transaction went awry, the scammers got angry.
"At that point I went, 'Hey I'm not talking to the bank... Wow, I have been scammed,'" James said.
It was the same con that hit B of A customers across the country... and like B of A's initial response to customers, Chase denied James's fraud claim -
"Their attitude is, if it's on Zelle, shame on you," James said.
Federal law requires banks to refund victims of fraudulent, unauthorized money transfers.
VIDEO: Bank of America gives refunds to some victims of growing Zelle scam
But Chase told James he authorized those payments - even if it was a scam.
And Zelle offers no fraud protections.
"There's no protection, there's no chargeback, there's no nothing!" James exclaimed.
What got him most? Chase's denial letter saying: "As we discussed and agreed, no action will be taken. This inquiry is now resolved."
"I definitely didn't agree and we definitely didn't discuss this outcome," James said.
B of A has refunded some victims of the Zelle scam. When we asked Chase about its policy, the bank only offered a warning that bankers will never ask you to send money with Zelle.