CHICAGO (CBS) — Nicole Saez says her bank is asking her to come up with proof that her phone was hacked. Otherwise, they can’t refund her for hundreds of dollars in Zelle transactions that she insists she did not make.

That’s a tall task, the kind that Morning Insider Tim McNicholas has been hearing about for months.

READ MORE: Tinley Park, Matteson Walk-In COVID Vaccine Sites Now Open

Picture this: a single mom in Norridge learns someone somehow transferred more than $1,700 from her bank account.

Nicole Saez said she got the email notifications last month while she was cleaning her son’s room.

“I had nothing left. I think there was $4 left in my savings,” she said.

Saez contacted Bank of America right away, but the bank told her the transactions appeared to have come from her device.

She said they suggested she call T-Mobile to get proof that she was hacked; a suggestion reiterated in a voicemail from Bank of America.

“At this point there really isn’t much further we can do, without proof of porting from your phone company to confirm the claim of hacking that you’ve provided,” the message said.

“I file a police report, I go by the book, but I have to find out who hacked into my phone and did this? I can’t do that. I don’t know how to do that,” Saez said.

READ MORE: Auburn Gresham Funeral Home Offering COVID-19 Vaccine

When she called T-Mobile, she says they told her they can’t do it either.

In 2019, we shared the story of customer who had to hire a computer expert to prove to Bank of America that she was hacked.

That worked, but federal law says when it comes to fraud claims the burden of proof should be on the banks.

“I can’t just hire people to go into my phone and see what happened,” Saez said.

A Bank of America spokesperson tells us they always follow federal law by thoroughly investigating fraud claims based on the information they can access.

The bank says if clients can provide additional information, like proof of a hack, they will reconsider their decisions and investigate further.

Banks typically send out one-time passcodes and other security measures for customers to access their accounts by phone or online, but hackers can sometimes find ways to bypass those.

CBS 2 also reached out to T-Mobile to ask if there’s anything they can do. They’re looking into it.

MORE NEWS: Deandre Binion Charged With Shooting 22-Month-Old Kayden Swann In Lake Shore Drive Road Rage Attack

UPDATE: More than two weeks after we first published this story, T-Mobile tells us it found no evidence that the customer’s line was compromised in any way.  So if or how hackers gained access to the bank account remains a mystery.

Tim McNicholas