Tom Singer joined the Federal Aviation Administration as an aerospace engineer in 2009. After a productive year writing safety regulations, he moved back to Florida and took a job with a private company.

Then he became Federal Debtor No. 2012390768A.

Singer, 32, did not borrow any money from the government, skip child-support payments or violate a law that would have his wages garnished. He was swallowed by the maw of federal bureaucracy when the FAA mistakenly sent him two paychecks after he left the government.

Almost four years later, he has not crawled out.

Singer resigned in October 2009 from the FAA’s Office of Commercial Space Transportation, where he worked on safety regulations for the commercial space industry. He and his wife moved back to Orlando, their home town.

Meanwhile, in Washington, an FAA clerk who was on vacation during the Christmas holidays in 2009 had failed to remove Singer from the government payroll. He eventually was taken out of the system in early 2010, but not before the FAA erroneously issued him two biweekly paychecks in December 2009.

When the first paycheck landed by direct deposit in his account at USAA Federal Savings Bank, Singer mistook the money for the accrued vacation leave he was expecting. After the FAA wrote him a letter explaining that he received a paycheck in error, he reimbursed the government his net pay of $2,059.49.

The problems started with the second paycheck, which landed in his bank account when he was on vacation. The FAA wrote to him demanding reimbursement, but for his gross pay of $3,091.20. It turned out that when the second check was issued, the agency had turned over his state and federal taxes to Virginia and the Treasury Department. It was too late for the FAA to recover that money, but the agency wanted it back.

Singer was told to pay a total of $527.21 for the withheld taxes and $107.48 in health insurance payments for benefits he had elected when he worked at the FAA but dropped when he resigned.

He balked. He was happy to return his net pay to the government. But he believed it was not his fault that the FAA failed to recover what it had withheld from a paycheck it should not have issued. The money would appear on his tax return as extra income, raising his taxable income.

“I said, ‘Okay, if you’re going to ask me to repay the money, it would be nice if you sent me an amended W-2 form,’” Singer said in an interview. “The government already has this money. Why should I pay it?”

He agrees the money belongs to the government. “But I deny I owe it to them. I’m, more or less, willing to work with them and say that any money I get back is money I’ll repay you.”

He requested an amended W-2 form and said that once he received it he would file amended tax returns for 2009 with the Internal Revenue Service and Virginia. Then he would repay his “alleged” debt to the FAA, he said.

The government did not agree with his logic. In March 2010, Singer asked the FAA for a waiver from the $527.21 debt. Eighteen months later, it was denied by the agency, which cited a decision by the comptroller general:

“We recognize that erroneous payments usually arise as a result of mistakes by those who are charged with the administrative responsibility for making the payments. However, where the payment made is in excess of the amount of pay authorized, the Government has the right to recover the excess amount.”

Singer, an engineer, is a meticulous and organized guy who does not give up. He saved every correspondence and document in his case — and even determined that he had overpaid the government $7.54. He appealed the denial of his waiver application. The FAA denied it in March of this year and told him to begin making arrangements to pay off the debt.

He said he received an amended W-2 form in 2011 for 2009, but it was inaccurate.

“I don’t want to make this sound like a sob story,” he said, “but my daughter had just been born and I was on paternity leave dealing with this paperwork.”

Then he received a letter from Treasury telling him his debt was in collection. The $527.21 had grown, by $150 in penalties, fees and interest and the $107.48 in health, dental and vision insurance payments for benefits he had elected when he worked at the FAA.

“I was told I was responsible for the insurance, but I stopped the benefits when I left the government,” he said. “Was I supposed to tell the insurance company at my new employer, ‘Hey, I’ve all of a sudden got an extra month of coverage from the FAA, can you just put my coverage and premiums on hold here?’ ”

Asked about Singer’s case, the FAA said in a statement: “While the FAA must ensure it is a good steward of public taxpayer dollars, it should not have taken this long for the agency to resolve Mr. Singer’s case. The FAA is committed to working with Mr. Singer to address the remaining issues quickly and close the matter.”

He has three years to dispute his tax withholding, a window that is closing fast.

“This has driven me crazy,” Singer said. “For now, I’m taking every avenue to fight it. For how long? I guess we’ll see how idealistic I am.”

He received a letter from Treasury recently informing him of the government’s intent to garnish up to 15 percent of his current wages to get its money.

He has asked for a hearing.