How much is on 1040 line 30 for the Recovery Rebate Credit? The IRS records show they sent it to you last March 2021. But you tried to claim it again. Line 30 is only if you didn't get the full amount or qualify for more.
Double check your bank statements and Check your IRS account (both accounts if married)
Your Online Account | Internal Revenue Service
If the IRS thinks they sent it to you but you didn't get it request a trace for a missing third Stimulus payment
https://www.irs.gov/newsroom/questions-and-answers-about-the-third-economic-impact-payment-topic-j-p...
