Please see this answer from AlanT222.
Recovery rebate credits may be claimed for individuals who died in 2020 or 2021 when filing the decedent’s 2020 tax return. This includes someone who filed joint tax returns with a spouse who died in 2020 or 2021. Please refer to the Form 1040 and 1040-SR instructions for more information.
Stimulus payments were advances on the Recovery Rebate Credit.
If you received the full amount of both stimulus payments (Economic Impact Payments), you won’t get any additional credit on your return this year since you’ve already received the full amount of the credit as stimulus payments.
