CHICAGO (CBS) — When people get the COVID-19 shot, it’s free – or at least it’s supposed to be at no cost.

But that is not the case for many people who got the vaccine at one Chicago hospital. CBS 2’s Tim McNicholas has been following the case of the bogus bill.

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“I saw there was mail from Weiss Hospital, and my immediate thought was maybe they’re inviting me to come in for a booster shot,” said Jeffrey Rovner.

Rovner thought he’d just gotten the golden ticket in the mail. Instead, it was a punch to the gut.

“I was pissed,” Rovner said. “I had no intention of paying.”

Weiss Memorial Hospital had sent Rovner a bill for $141.

“The fact they’re sending out a bunch of bills to people for the COVID vaccinations – I mean…” he said.

The August bill doesn’t say it’s for the COVID vaccine. It just demands a bunch of money for something that supposedly happened way back in March.

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“Every other medical bill I’ve gotten has indicated what it’s for,” Rovner said. “This is the first time I’ve gotten medical billing without any indication what the bill was for.”

Rovner is not even a patient at Weiss hospital. He played medical detective and realized he got his COVID shots there.

The second one was on the same date as the service date on his mysterious bill.

“Someone needs to get a grip on their billing system or question their intentions,” Rovner said.

A Weiss spokesperson told us there was “a system error” that caused some patients to be “mistakenly billed” for the COVID-19 vaccine. The hospital said it is “working to correct this error.”

“Hopefully, people will see this and not go ahead and pay this bill,” Rovner said.

It is a good lesson for everyone – to check your bills before blindly paying them.

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Weiss assures us they plan to contact every patient who was mistakenly billed, to tell them there will be no charge for the COVID vaccine.

Tim McNicholas