How would you and your family be affected if Congress does not pass another stimulus package? CNBC Make It would like to talk to you. Email money reporter Alicia Adamczyk at alicia.adamczyk@nbcuni.com.

Enhanced unemployment insurance has been a lifeline for many households in the U.S. over the past few months — if they've received the benefits.

Real time data on jobless benefit payouts are hard to come by. But data collected by the Century Foundation, a progressive think tank, indicates that the payments have lagged for potentially millions of workers for months because "antiquated" state payment systems have struggled to keep up with the record-setting number of workers seeking jobless benefits.

Some workers are still waiting on their benefits from March, Michele Evermore, senior policy analyst at the National Employment Law Project, tells CNBC Make It. 

While Congress has yet to extend enhanced unemployment payments — and states figure out how to comply with President Donald Trump's executive order — workers who were certified for benefits prior to July 25 (or July 26 in New York) and have been waiting to be paid will still receive the extra $600 per week retroactively. (If you were laid off after that, you do not qualify for the enhanced benefit.)

"If somebody qualified and they applied back when they lost work, the state should have to pay the benefit back to when they applied," says Evermore. "You've earned a benefit and they have to pay it to you if you're eligible."

That's applicable to a sizable number of claimants: Around 40% of new applicants had not yet received a benefit payment by the end of June, according to the most recent data collected by the Century Foundation. That's around 15 million people. 

The best way to get the benefit is to keep contacting your state unemployment office to make sure that your application did not have errors, says Evermore. However, that can be a difficult and time-consuming process, she warns, which may deter some from pursuing their benefits. A single mother of five in Florida told the Washington Post that she called her state's Department of Economic Opportunity 400 times in April alone to work out why she hadn't yet received a UI payment. She wasn't able to get through to anyone.

But if you're able, keep at it, Evermore says. And make sure to recertify each week that you're unemployed so you get the benefit you're entitled to. If you can't get through, try contacting your state representative or join a Facebook or Reddit community where people share tips with each other.

"This is your money, you've earned it," says Evermore. "It's there for exactly this kind of circumstance."

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