After you file

I am trying to file an amended return (form 1040-X) after receiving an additional unexpected 1099-R.

Line 5B on form 1040-X (net change of taxable income) is almost double the amount of taxable income shown in box 2A on the 1099-R that I received after filing my original tax forms.

Line 15 (Taxable Income) on my original filing of form 1040-SR has increased by almost double the amount on the additional 1099-R.

TurboTax must be miscalculating the additional income.