The federal government is attempting to recoup almost $7 million from more than 1,200 people who retired from the Navy after it discovered a system error had given them larger monthly payments than they were due for almost four years, officials said Monday.

The Navy Times first reported the error, which resulted in incorrect service time calculations for 1,283 retirees from August 2019 to February.

That error created a total debt of about $6.8 million, according to new data obtained by NBC News. The personal debts incurred range from $35 to more than $70,000, the Defense Finance and Accounting Service said Monday.