If you claimed you did not get some of the first 2 stimulus payments but the IRS disagrees then you will have to initiate a trace of the missing money.
https://www.irs.gov/coronavirus/second-eip-faqs#paymentlost
https://www.irs.gov/newsroom/2020-recovery-rebate-credit-topic-g-correcting-issues-after-the-2020-ta...
https://www.aarp.org/money/taxes/info-2020/how-to-find-missing-stimulus-payment.html
