Families shopping for health insurance through the new federal marketplace are running into trouble getting everyone covered when children are eligible for Medicaid but their parents are not.

Children who qualify for Medicaid, the safety-net program for the poor and disabled, can’t be included on subsidized family plans purchased through the federal marketplace, a fact that is taking many parents by surprise and leaving some kids stuck without coverage.

A California man says he was given false assurances that his children could be covered by the same plan he picked for his wife and himself, and a Florida father says his daughter is going without coverage while he waits for answers.

And in New Hampshire, some parents who’ve enrolled in private plans for themselves alone are finding out later that their children aren’t eligible for Medicaid after all, leaving their kids with no options.

“The children are getting stuck in this spot where we’ve enrolled the parent, but we can’t bring the children back on the family plan,” Maria Proulx, senior legal counsel for Anthem Blue Cross and Blue Shield of New Hampshire, told a state advisory board panel this month.

The federal Centers for Medicare and Medicaid Services declined to say how the system is supposed to work for families and what problems have emerged. But a regional manager for CMS acknowledged the problem at the same New Hampshire meeting and said the agency is working on it, as did Proulx in a later interview.

“This is an important issue, and we’re not taking it lightly,” she said. “Even if this impacts only one family … it’s a big deal and we want to get it resolved as quickly as possible.”

The federal government sets minimum guidelines for Medicaid eligibility, but states can choose to expand coverage beyond that. In some states, parents must have significantly lower incomes to gain Medicaid coverage for themselves than they would to get coverage for just their children, either through Medicaid or the Children’s Health Insurance Program — also known as CHIP — the low-income health insurance program for children who don’t qualify for Medicaid.

In North Port, Fla., Russell Clouden was thrilled to find a better, cheaper family plan through the new marketplace, then stunned to realize his 14-year-old daughter wouldn’t be enrolled because she might qualify for Florida Healthy Kids, the state’s version of CHIP. The federal government still hasn’t transferred roughly 90,000 Medicaid files over to Florida officials, including Clouden’s daughter’s, so she still doesn’t have insurance.

“Based on your income, they’ll separate your kids from your primary policy and they shift them off to Medicaid or Healthy Kids and there’s no way you can bring them back,” said Clouden, whose daughter is an accomplished equestrian jumper.

“I’m kind of in limbo with her because I’m just hoping she doesn’t get injured or sick,” said Clouden, 53, who runs a restaurant franchise. “Without insurance, you’ve kind of got a knot in your stomach watching her jumping.”

Insurance broker Matthew Dinkel in Fort Myers, Fla., said he has about 15 clients in Clouden’s position.

“I have worried parents literally calling and texting me every day asking for an update,” said Dinkel. “They canceled their old plans that covered their entire family and now they have coverage but their kids don’t.”

Jessica Waltman of the National Association of Health Underwriters said her group has raised the problem, and others, with federal officials and asked for a dedicated hotline or email address for insurance brokers to get answers.

“It’s a nationwide issue that we’ve heard time and again, and it could have very significant coverage issues for families,” she said.

Marc Jobin, a construction consultant in southern New Hampshire, said the process has been so confusing, he’s put off a decision for himself, his wife and their two children, even though he’s seen premiums that are significantly lower than what they pay now.

“We’ve been hesitating for two months now because the information is not clear,” he said. “Around the holidays, we were thinking, ‘let’s do this, let’s sign up,’ and then the latest problem is now our children will probably be thrown into the state health care system, but nobody knows what that means.”

Mary Ann Cooney, associate commissioner of the New Hampshire Department of Health and Human Services, urged those awaiting Medicaid decisions to call their state offices directly. She said her office has been getting incomplete application information from the federal government, making it harder to contact people to determine their Medicaid eligibility, but situations are improving and the office is reaching out to hundreds of people each day.

“There’s a real light at the end of the tunnel,” she said.

But in the meantime, children are going without coverage. In California, Robert Clark said when he applied by phone through the Covered California marketplace, he was assured that his two children would be on the plan he picked. But he later got separate notices from the insurance company and Medi-Cal, the state’s Medicaid program.

He called Covered California again and was told the person he’d previously talked to there was wrong and that his children had to be enrolled in Medi-Cal. Clark, the president of a Menlo Park technology company, doesn’t like that prospect because the doctors his children have seen since their births don’t take Medicaid.

“It’s pretty frustrating,” he said. “We’ve probably spent several days’ worth of time on hold.”

Instead, he’s exploring whether he can enroll his children in individual, unsubsidized plans through Covered California. He recently found out his original application was “hung up,” so he plans to resubmit a fresh application, but in the meantime has lost out on coverage for January.

“My daughter is in gymnastics,” he said. “If she falls on her head, we need to be covered.”