CHICAGO (CBS) — Over the past few months, we’ve reported on and investigated dozens of issues with your mail.

On Tuesday, we shared with you the frustrations of some people of those living an Edison Park neighborhood building who are now being told they need to pick up the mail from the Post Office.

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We’ve also reported on numerous scams targeting your mail. Some people have reported receiving unemployment debit cards for other people – or strangers’ Social Security numbers.

Also Tuesday, CBS 2’s Chris Tye reported on a new scam – underlining the desperation of the coronavirus pandemic. Checks – six figures’ worth – are disappearing in one ZIP code, and the Post Office has a warning.

It was a week after Halloween. Items destined for this small office park just north of Midway International Airport, made up of meat markets and cleaning companies, began to vanish.

“It started out very slowly,” said Ken Pecho of packaging operator Combined Sales Company. “All the way through December and even into January, we were seeing more and more incidents.”

The incidents started out incidental, but they have now become costly.

“Checks that were sent to us from customers didn’t make it to us, but were fraudulently cashed,” Pecho said.

Crooks affixed bogus signatures.

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Diana Pizana, never an employee of Combined Sales Company, signed over money to herself on Nov. 9. Betty Miller did it three days after that, and what looks like a scribbled “Kevin” deposited a bundle Christmas week.

“There were over $35,000 in checks that never made it to us,” Pecho said.

That’s just at Combined Sales. Over $100,000 in slippery sign-overs have been deposited since the fall from that business park near Midway alone.

“The only thing that made sense was that there was an issue with the Post Office,” Pecho said.

The USPS confirms to CBS 2 the scam is growing, warning operators there has been an uptick within the Chicago area.

Two investigations have begun within the USPS to find out what is going on inside ZIP code 60632, and where the sticky fingers of Diana, Betty, Kevin, Tamela, and Vize first get their hands on the checks intended for that small office park just north of Midway where none of them work.

“Whether in the main branch or the local branch, they’re selling them off to individuals who are opening accounts, depositing checks, then cleaning out the accounts,” Pecho said.

The total number of checks stolen on that one business park alone totals in the dozens. We are told all those companies have been made whole by their banks.

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The investigation continued late Tuesday. So far, no arrests have been made.