Update: Chase says the nearly $1 billion was actually a negative balance. Read the full updated story.

LARGO, Fla. (WFLA) – Julia Yonkowski went to her local Chase Bank in Largo on Saturday to withdraw some money, but she wanted to check her balance first.

According to the bank receipt she received, Yonkowski had $999,985,855.94 in her account.

As you can imagine, being shocked was an understatement.

“Oh my God, I was horrified. I know most people would think they won the lottery but I was horrified,” she said.

She originally went to the ATM just to grab $20.

“When I put in for the $20, the machine came back and said we’ll give you the $20 but that’ll cause an overdraft and you will be charged and I said, ‘Oh just forget it,'” she said.

She hasn’t touched her account since Saturday night.

“I know I’ve read stories about people that took the money or took out money, and then they had to repay it and I wouldn’t do that anyway because it’s not my money,” she said.

Yonkowski also told 8 On Your Side’s Olivia Steen she worries that her own money could be compromised.

“It kind of scares me because you know with cyber threats. You know I don’t know what to think,” she said.

Since becoming a temporary billionaire, she’s tried several times to reach out to Chase Bank.

“I just can’t get through. I get tied up with their automated system and I can’t get a person,” she said.

8 On Your Side also reached out to Chase Bank, but no one was available to speak on Sunday.

Yonkowski said she’s heading to the bank first thing Monday morning in hopes of clearing everything up.

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