DETROIT — Fiat Chrysler Automobiles says it overpaid about 24,000 hourly employees while their plants were shut down and has told them to either pay back the extra amount or have it deducted from future paychecks.

On average, the workers received $500 more in supplemental unemployment benefits than they were contractually entitled to, FCA said. The overpayments occurred because a federal coronavirus relief program retroactively increased the workers’ government unemployment checks for the week ending April 4, taking their total compensation above the level that FCA’s contract with the UAW requires during a temporary layoff.

Workers are supposed to receive 74 percent of their usual 40-hour pay, with FCA making up the difference between that amount and their government unemployment check.

Employees can repay the overpayments either through a lump sum or with a $100 payroll deduction per week. FCA spokeswoman Jodi Tinson told Automotive News in an emailed statement that “many have already” repaid the overage in a lump sum, but she declined to give an exact number.

UAW spokesman Brian Rothenberg said that although workers might be unhappy with FCA’s request, he didn’t know of any grievances that had been filed over the matter.

“I’m not aware of a grievance, yet,” he said Thursday. “Now, that doesn’t mean there hasn’t been, but I’m not aware of it.”

The Detroit News reported on the overpayments on Wednesday, citing a letter from FCA to the affected employees. General Motors and Ford Motor Co. told the newspaper that they reduced supplemental unemployment payments when the higher government payments started, so no overpayments were made.