I want to change that i made payments last year

If you mistakenly entered estimated tax payments made during 2018 and you need to delete them, then follow the directions below.

1. Log in and click take me to my return (unless already in).
2. Click Tax Tools from the left-side menu.
3. Select Tools from the drop-down menu.
4. Click the Delete a Form hyperlink and select Delete next to the Estimated Taxes and Form W-4 Worksheet.