To access your prior year online tax returns sign onto the TurboTax website with the User ID you used to create the account - https://myturbotax.intuit.com/
Start the 2024 online tax return by entering some personal information then click on Tax Home on the left side of the screen.
On the Tax Home webpage -
Scroll down to the section Your tax returns & documents. Click on the Year 2023 and Click on Amend (change) return
If the link to amend is not active, clear cache and cookies on your web browser. If that does not correct the problem then change your web browser to one of these that you are not currently using, Google Chrome, Mozilla Firefox, Microsoft Edge