IRS Stimulus Check News: American taxpayers who missed claiming the $1,400 Recovery Rebate Credit for 2021 are urged to act before the April 15 deadline. While over $1 billion in unclaimed refunds remains, filing taxes on time is crucial to avoid penalties. The IRS warns that attempting to claim funds twice may result in penalties, interest, and complications in future returns. Eligible individuals must ensure they file their taxes promptly to secure their payments before the money is returned to the U.S. Treasury.