Why can't I E-file my taxes even though I checked the box stating that I received Stimulus checks back in 2020?

The current online software is only for 2022 returns.  There are NO questions about stimulus checks for a 2022 return.   If you are trying to use online for a 2021 return your return is all wrong and must not be filed.  Clear it out and save the account to prepare your 2022 return.

If you are trying to prepare a return for 2020 or 2021 you need to be using the CD/download software for the specific year.   There will be questions for the stimulus checks in Federal Review for a 2020 or a 2021 return.

Online preparation and e-filing for 2019 and 2020 and 2021 is permanently closed.

To file a return for a prior tax year

 If you need to prepare a return for 2019, 2020 or 2021 you can purchase and download desktop software to do it, then print, sign,  and mail the return(s)

https://turbotax.intuit.com/personal-taxes/past-years-products/

You may also want to explore purchasing the software from various retailers such as Amazon, Costco, Best Buy, Walmart, Sam’s, etc.

Remember to prepare your state return as well—if you live in a state that has a state income tax.

https://ttlc.intuit.com/community/state-taxes/help/how-do-i-contact-my-state-department-of-revenue/00/25573 

When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s.  Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS/state received the return.

Federal and state returns must be in separate envelopes and they are mailed to different addresses.  Read the mailing instructions that print with your tax return carefully so you mail them to the right addresses.

Note:  The desktop software you need to prepare the prior year return must be installed/downloaded to a full PC or Mac.  It cannot be used on a mobile device.