You can correct this by amending your returns. There's nothing specific on your tax return that needs to be reported for a Roth 401(k) contribution.
It is too early to amend 2024. Use this tool to check availability of forms, including 1040X: Tax form availability.
You can amend 2023 now. Here is how to do this in TurboTax Online, from How do I amend my federal tax return for a prior year?:
- On the Tax Home screen, scroll down to Your tax returns & documents and select the year you want to amend.
- Select the Amend (change) return dropdown, then Amend using TurboTax Online.
- Continue through the screens, make the changes you need to make (delete the Roth IRA input), and carefully answer the remaining questions to finish amending your return.