(The Hill) – As many as 10 million people may still be entitled to receive a COVID-19 stimulus payment, the government’s internal watchdog said.

Americans with little or no income, who are not required to pay taxes, have until Nov. 15 to complete a simplified tax return in order to get their stimulus checks, the Government Accountability Office (GAO) said in a blog post.

“Throughout the pandemic, IRS and Treasury struggled to get COVID-relief payments into the hands of some people — especially those with lower-incomes, limited internet access, or experiencing homelessness. Based on IRS and Treasury data, there could be between 9-10 million eligible individuals who have not yet received those payments,” the agency said.

The GAO found that people who don’t have to file tax returns, first-time filers, mixed immigrant status families and people experiencing homelessness were among those likely not to have received a payment owed to them.

Over the course of several payments delivered through legislation enacted under both the Trump and Biden administrations, $931 billion went out to Americans to help with the economic fallout from the coronavirus pandemic.

However, the GAO described this process as “challenging for the IRS and Treasury.”

Many in the tax world have come to the defense of the IRS over the course of the pandemic, saying it was beyond the call of duty for a tax collection agency to become the primary administrator of emergency economic stimulus payments.

Still, the added duties for the IRS have led to a backlog of tens of millions of unprocessed tax returns and unanswered phone calls that have left millions of Americans waiting for their annual refunds.

The extra pressure may also have resulted in the stimulus delivery shortage for up to 10 million Americans.

“Part of the challenge for the IRS and Treasury in 2020 was they only had data on taxpayers that had previously filed taxes,” the GAO said. “In May 2021, the Treasury Inspector General identified potentially 10 million individuals eligible for payments. As of June, IRS had no plans to conduct additional outreach.”

A recent spending package from Democrats is set to give the IRS its biggest funding boost in decades, with $80 billion going to the agency in the next 10 years.

While more than half of that will go toward increased enforcement efforts like audits, around $33 billion will go toward operational support, services for payers and systems modernization.