I am trying to fix this tax return rejection and its not letting me change anything. I don't know what to do.

To access your current or prior year online tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/

When you sign onto your online account and land on the Tax Home web page, scroll down and click on Add a state. 

This will take you back to the 2023 online tax return.  You can change anything in the tax return once you have accessed the 2023 return.

what is the full rejection mesage and code, if any. We may be able to help but some issues cannot be fixed and require you to mail in your return. with the free edition there would be a charge to talk to Turbotax support.