Can i go back to my AGI on the 2023 taxes i am filing now?

See this TurboTax support FAQ for entering the AGI - https://ttlc.intuit.com/turbotax-support/en-us/help-article/tax-return/correct-2020-agi-turbotax-online/L8CM2xq5K_US_en_US?uid=lvigosx9

How to correct the AGI in the Online version
https://ttlc.intuit.com/community/agi/help/where-do-i-correct-my-agi-in-turbotax-online/00/26311

Did your efile reject?

Try entering 0 for the AGI. The IRS might have processed your return later so the AGI didn't get entered in time.  Especially if you mailed it.  That works for most people. See,
https://ttlc.intuit.com/community/rejections/help/what-if-i-entered-the-correct-agi-and-i-m-still-getting-an-e-file-reject/00/27031