The Recovery Rebate Credit on 1040 line 30 is if you didn't get the 3rd Stimulus payment .
Did you not get the 3rd Stimulus payment that was 1400 per person last March 2021? Or qualify for more? 1040 Line 30 is only if you didn't get the full amount or qualify for more. The IRS shows they already sent it to you. Turbo Tax asked you how much you already got. And the IRS sent out letter 6475 telling you how much the sent you. A letter to each spouse for half for married.
A lot of people forgot they got the deposit last March - May 2021. Or missed one payment and entered the wrong amount. Then when the IRS reduces their refund and they check their bank accounts they have been finding the payments.
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...
