The stimulus check is an advance on a credit you can receive on your 2020 tax return. If something went wrong or you did not get the stimulus check in 2020, you can get it when you file your 2020 return. Did you file a 2020 return?
The Recovery Rebate Credit will be found in the FEDERAL REVIEW section. ( you should see "Let's make sure you got the right stimulus amount”) If you are eligible it will end up on line 30 of your 2020 Form 1040.
Make sure that you enter ALL of the stimulus money received for the 1st and 2nd stimulus for yourself, your spouse and your children.
https://www.irs.gov/newsroom/economic-impact-payment-information-center-topic-j-reconciling-on-your-...
There is no place to enter anything about the 3rd stimulus payment on a 2020 return. If you did not get that one you can get the credit on your 2021 return if you are eligible.
