City tax collectors say data and software issues led to thousands of Norwalk residents having higher car tax bills than they deserved.

It is estimated that nearly 4,000 bills have been impacted by the issue.

Doris Dejesus told News 12 she opened her car tax bill and noticed a large increase this week.

"It looked like it doubled. It was extremely high,” she said. “I started hearing from other people, same thing. So, I'm like, ‘Is this correct?’ I started wondering if something was wrong."

City of Norwalk Communications Director Michelle Woods apologized for the inconvenience and says it will be corrected.

"The city's tax assessor and tax collectors' office made us aware that approximately 5% of resident have been impacted by inaccurate tax bills,” she says.

Woods says the tax assessor and tax collector’s office converted to a new software earlier this year.

"Some of the conversion issues are causing these inaccuracies,” she said.

Officials also say some residents may not have received the elderly or disabled tax credit that they typically get.

"A subset of individuals who qualify for the elderly or disabled tax credit program were impacted with an inaccurate tax bill,” said Woods.

The tax assessor’s office says it is adjusting and will be sending out corrected tax bills to all impacted residents.

City leaders also encourage residents to check on the city's website under the tax collector section.

Residents have until Aug. 7 to pay the tax bills by mail, in person at City Hall or over the phone with the tax collector’s office.