PITTSBURGH (KDKA) – The app Pittsburgh Parking Authority uses has had a data breach affecting 21 million users.

It’s a popular phone app that makes it easy for Pittsburghers to pay to park. But the city’s Parking Authority says hackers broke in and stole information several weeks ago.

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The Pittsburgh Parking Authority says users’ emails, phone numbers and license plate numbers were leaked, but not their credit card information.

So many Pittsburghers use this app, and now they’re being urged to change their passwords.

Here’s how it works: you park and walk up to the nearest meter. A number on the side correlates to your parking zone. To link the two, you need to put in some personal information and hackers know that.

It’s an app that’s popular with busy and tech-savvy Pittsburghers.

“No one carries money or coins really anymore. So the parking app is definitely nice and you check it on your phone and see how much time you got left,” said Brennan Oppman, who uses the app.

But with convenience comes risk.

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And Dave Onorato with the Pittsburgh Parking Authority wants to know why there was a delay to notify customers.

“They haven’t given me an answer yet, but I do have that question to them,” said Onorato.

Onorato says he just learned hackers only got access to email addresses and license plate numbers. He says the city teamed up with the parking platform ParkMobile more than 5 years ago.

“I guess country-wide they had over 21 million customers that were breached and they informed that there was not credit card information breached,” said Onorato.

No credit card information and no social security numbers, he said.

Users of the app KDKA talked to didn’t seem phased.

Onorato said the app is supposed to notify people Wednesday and recommend you change your password.

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The app is used in Pittsburgh, Philadelphia and Lancaster, along with other large cities.

Meghan Schiller