The department revealed in January that the number consisted of both those who qualified for the initial $1,200 direct payments that were part of the CARES Act that passed in March 2020 as well as the $600 direct payments that were issued in December.
These payments were sent by the Internal Revenue Service (IRS) based on data collected from 2018 and 2019 tax returns. But up to 8 million people who qualified for the payments did not receive them because the IRS did not have their information on file.
Although it's been more than one month since Taxpayer Advocate Service, an independent organisation within the IRS, called attention to the issue, there has still not been a thorough solution to get Americans their stimulus checks.
The only way for people to get the payments now would be on their 2020 tax return by filing for the Recovery Rebate Credit, CNN reported. "This approach – forcing eligible individuals to forgo receiving an EIP that was exempt from offset if paid timely – is a problem the law and the IRS have created," the TAS said.
Online tools were created last year for people to receive their stimulus checks through direct payment, but the IRS also allowed for taxpayers to receive the money by claiming it once they filed their taxes. But what wasn't as clear to the public was that filing for the payment could result in a lesser amount than receiving it through direct payments.
To address some of the payments that have not been cashed by the public, the IRS sent out debit cards to people across the country with their stimulus payments on them last summer. But some people threw them out because they believed it was "junk mail".
People missing out on the payments were "very low-income Americans who normally don't file taxes" or people who moved bank accounts following filing their 2018 or 2019 taxes, CNN reports.
"Financially struggling taxpayers who were entitled to receive the full amount of the EIP last year but did not have effectively been harmed once," the TAS said online. "It is unfair to harm some of these taxpayers a second time by seizing some, or all, of their stimulus payments."
A TAS spokesperson told CNN that the agency was still working out different ways to target Americans who have yet to receive a stimulus payment.
The IRS sent out 160 million payments totalling $270bn after the CARES Act initially passed in March. Then an additional 147 million payments that were worth $142bn were sent out two days after then-President Donald Trump authorised the $600 stimulus checks in December.
On Saturday, the US Senate approved President Joe Biden's $1.9tn American Rescue Plan, which would send $1,400 checks to some Americans as another round of stimulus payments amid the coronavirus pandemic.
The bill is being sent back to the House to vote on, and Mr Biden could sign it into law by the end of the week.
The White House revealed on Monday that Americans could then receive the new round of stimulus checks by the end of March. But the Biden administration has not revealed if issues getting some Americans the money would be fixed for this round of checks.