WASHINGTON » Just days before the Obama administration’s self-imposed deadline to fix the troubled federal health insurance website, officials said Monday that they were aware of another problem that has prevented thousands of people who were unable to verify their identity from shopping for health plans.

Many users of the website have had their applications cast into limbo after they uploaded copies of documents like driver’s licenses, Social Security cards and voter registration cards, or sent them to the office of the federal insurance marketplace in London, Ky.

Administration officials said the government had established strict procedures to verify that people applying for insurance were who they said they were, in order to prevent fraud and identity theft. But a breakdown in the process instead is causing concern among some consumers about the handling of their personal information.

"I am in no man’s land," said Roger N. Hampton of Boca Raton, Fla., who filed an application early last month. "I have been waiting patiently for my ID verification to come through, which has not occurred thus far. So I can’t see what plans are available."

When he tried to file his application online, Hampton received a message that said: "Your identity wasn’t verified. You won’t be able to submit your application for health coverage until your identity is verified. Submit documents that prove your identity. Once you upload your documents, they’ll be reviewed. The results of your identity verification will be emailed to you."

Hampton hit a button that said, "Upload documents" and attached copies of his Social Security card and driver’s license. He said he had heard nothing back.

John W. Filbin of New London, N.H., reported a similar experience.

"I have applied multiple times, but am not able to enroll," Filbin said Monday in an interview. "I have been stuck in identity proofing since early October."

On Friday, the Obama administration announced that it would give people eight more days, until Dec. 23, to sign up for coverage that takes effect Jan. 1.

But Filbin said: "We don’t need extra time. We’ve been ready since Oct. 1. I have emailed and hard mailed my driver’s license. We’ve made our way through the slow and troubled website. Is there going to be a fix for us?"

People who cannot establish their identity by answering certain questions at HealthCare.gov are instructed to call the help desk at Experian, a credit reporting agency, for "ID proofing."

Customer service representatives for the federal marketplace and for Experian said they had received calls from many people who were unable to verify their identities, and internal government documents show that lower-level federal employees have known of a problem for weeks.

Joanne Peters, a spokeswoman for the Department of Health and Human Services, said she did not know the extent of the problem.

"People have personal circumstances that could prevent their identity from being verified online," she said.

Filbin said he had called Experian but got no help because he did not have a "reference number." Experian sent him back to HealthCare.gov, which has repeatedly indicated that his identity verification is "in process," with no date set for completion.

Jo Ann Fields of Felton, Del., appears to be lost in the same labyrinth.

"I mailed a copy of my voter registration card on Oct. 24, and I have not heard anything back," Fields said. "I uploaded the voter registration card, and they said I would get an email response. I have had no response. I called the health insurance marketplace — 800-318-2596 — and they say to give it more time. My application is stuck in ID verification."

Consumers said they worried that their identification papers were falling into a black hole. Fields said she imagined "a bag of mail sitting on somebody’s desk in London, Ky., with my voter registration card in it." Insurance agents and brokers who want to help people enroll in the federal marketplace also need to go through "identity proofing," and they say they, too, have experienced difficulties.

Filbin said the experience was particularly annoying because "I am in favor of the Affordable Care Act," and he added: "I was an Obama supporter. I think I still am, but a little less positive."

Experian is based in Dublin. Two spokesmen for the company, Gerry Tschopp and Michael Troncale, said they could not discuss Experian’s work for the federal insurance program because of restrictions in its contract with the government.

The federal website says identity verification is needed to protect consumers’ personal information.

"Without this process," it says, "an unauthorized person could create an account and apply for health coverage in your name without your knowledge."

Consumers are asked questions that, according to the government, only they can answer. The questions are based on information in their credit reports — even though federal officials expect to receive many applications from young people and low-income people with little credit history.

The administration said that the website had another "unscheduled outage" Monday, for about an hour. Still, administration officials said they were on track to meet their commitment that HealthCare.gov would "work smoothly for the vast majority of users" by Saturday.