“I celebrate my kids’ birthdays over the phone. Why?” Hervias said.

While some medallions are held by large owners with fleets, owning a single medallion was long seen as a ticket to the middle class for immigrants like Hervias, who is from Peru.

Many of them now owe more on their medallion loans than they originally paid for the medallions because they used their equity in the medallion for a home, a child’s education or other expenses.

Hervias said he borrowed against his medallion to pay for medical care for his mother, a new car and a visit to his homeland.

“Every time we want to go on vacation or do something, where do we go? To the equity of the medallion,” he said.

Other medallion owners tell similar stories.

Constant Granvil bought his medallion for $102,000 in 1987 and said he now owes more than $300,000 to his lender. He could have sold the medallion for two or three times that a few years ago, “but I said no, I’m not going to sell it,” said Granvil, who is 76. “And then I got caught.”

The value of Granvil’s medallion is hard to pinpoint because 2017 sale prices have varied from the $200,000s to the $500,000s depending on whether lenders are willing to finance the purchase.

Meanwhile, Granvil, who no longer drives because of poor health and uses a broker to hire a driver, said he is facing threats from the lender, Melrose Credit Union, to foreclose on not just his medallion, but also his house.

“How am I going to live?” he said. “And now Melrose wants to take my house?”

The New York State Department of Financial Services took possession of Melrose Credit Union in February and appointed the NCUA as conservator.

Critics say the federal agency is playing hardball with medallion owners like Granvil, who have been making their payments, by demanding that they pay off their loans in full or face foreclosure.

“They’re approaching it with this cookie-cutter idea,” said David Beier, head of the Committee for Taxi Safety, an association of taxi leasing agents. “They want you to mortgage your house to them as collateral. It’s forcing borrowers into bankruptcy.”

John Fairbanks, a spokesman for the NCUA, said that the agency has hired a management team to run Melrose and that it would be inappropriate to comment on the management team’s actions.