Next question for customers: Are you really enrolled?

The federal government may say it has improved but insurers say they are not so sure. And customers signing up for health insurance need to make sure they really are covered. The key? Look for the orange pop-up notice.

Lots of people may be in that position. A senior administration official told NBC News that 750,000 people had visited the site as of 5.30 p.m. Eastern time Monday. 

Visits don't equal enrollments, but it's a far higher number of visitors than the site's been forced to handle since the first few days of its disastrous launch. Jon Elswick

The so-called back end — where the actual business of paying for and getting enrolled in insurance takes place, isn’t working perfectly. Officials say they’re aware of it, and reminding people to make sure they are, in fact, fully enrolled.

“When a consumer selects a plan and enrolls in marketplace coverage, an orange message is clearly displayed letting them know that they must make payment to be covered,” said a spokesman for the Centers for Medicare and Medicaid Services, which is running the website.

“If a consumer doesn’t receive that notice or is unsure as to whether they successfully enrolled, they should contact our call center or the insurer of their choice. The consumer will then be contacted by their insurer on how and when to make payment.”

CMS spokeswoman Julie Bataille said the agency will try to confirm that those who have enrolled know their next steps to ensure they are covered.

Robert Zirkelbach of America’s Health Insurance Plans, an industry group, says forms called “834s” are still glitchy. They are a kind of digital enrollment form that conveys crucial information about new customers to the insurance company. “Health insurers are still seeing enrollments that are duplicated, missing information, things like that," Zirkelbach said. 

CMS officials say they’re working on it. "We have fixed many of the bugs that led to the 834 issues," Bataille said Tuesday. She said a single bug involving social security numbers caused 80 percent of the problems, and had been fixed.

This past weekend was the government’s self-imposed deadline for fixing the faulty website. Jeff Zients, the incoming White House economic adviser named by President Barack Obama to lead repair efforts, gave his team’s efforts a glowing review on Sunday.

“After clearing through fewer than 100 bugs across the entire month of October, the speed has more than tripled, with over 400 bugs fixed,” Zients told reporters in a telephone briefing.

He said was now working more than 90 percent of the time and up to the promised capacity of 50,000 users at any given time. Bataille said traffic slowed the site down Monday morning, with error rates going up and response time going down. 

When about 30,000 users were on the site at one time Monday morning, the technology team deployed a new queuing system that tells users the site is too busy and offering to send them an email when traffic eases, Bataille said. 

That's fewer users than the promised 50,000 at once but Bataille declined to say so directly.

Separately, a person familiar with the numbers who declined to be identified because he was not authorized to discuss them said an estimated 100,000 people had been able to choose a health plan using the federally run site in November. That compares to around 27,000 in October, and far fewer than what officials had hoped for. 

New York reported on Monday that 91,103 New Yorkers have managed to fully enroll on that state's site. "Of these enrollees, 50,119 have enrolled in a Qualified Health Plan and 40,984 have qualified for Medicaid," the state health department said in a statement. 

The White House will officially report the November enrollments in mid-December. Officials say the numbers must be “scrubbed” to make sure they are accurate. In the meantime, the best way to tell how things are going will be in anecdotes, says Larry Levitt of the Kaiser Family Foundation. “We will see if people are being helped,” he said.

It was the litany of first-person stories that fueled the heavy news media coverage about people losing their private plans, Levitt said. On top of having their plans canceled, their best hope for finding alternative care was the balky website. “It was so hard for people to find out what their options are,” he said. 

Obama relented and said the federal government would allow private insurers to continue issuing plans in 2014 even if they didn’t meet the new, strict requirements for coverage — although it’s been left to the states to decide whether they really can.

The White House and CMS were preparing, and hoping, for a rush of enrollees in December. Experts say experience shows that Americans tend to wait until the last minute to sign up for health insurance. Plus, the Obama administration slid the open enrollment period back a little, giving people until Dec. 23 to sign up for coverage that would start on the first day possible, Jan. 1.

People have until March 31 to sign up for coverage and get credit for being covered in 2014. Anyone going without medical insurance in 2014 may have to pay a tax.

More than 40 million Americans lack health insurance and one of the primary goals of the 2010 Affordable Care Act was to get them covered — either by buying tightly regulated, private insurance on the exchanges, or by getting expanded Medicaid in the states that choose to expand it, or through an employer under new requirements for covering workers.

CMS officials say the website’s repair is an ongoing process. Zients leaves for his job at the White House in January and White House spokeswoman Jennifer Palmieri said he will be replaced, but didn’t say whether there is a candidate.

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