How do I amend misfiled tax for last year and this year (2018 and 2019)?

[wmh408]

I have an investment that paid back in both 2018 and 2019, however I just noticed that for both years, they have already withheld the tax portion, and issued us Form 8805 (Foreign Partner’s Information Statement of Section 1446 Withholding Tax), probably because most of the other investors are foreign partners, but we are not.
For both years, we have reported the already taxed income in our K-1, so we are double taxed. We have not filed our tax this year yet, how do we amend both last year and this year's income?

[DawnC]

Since you have not filed 2019 yet, you can enter the amount of withholding before you file.  Withholding on Form 8805 should be included on Line 17 of your Form 1040.   In TurboTax, go to the Deductions & Credits list.  Then scroll down to Estimates and Other Income Tax Paid.  Within this section, you will find Other Income Taxes Paid in 2019.  Then click on Update next to Withholding not already entered on a W-2 or 1099.  

You will need to amend your 2018 tax return to report the withholding since you have already filed that return.  To amend your 2018 tax return, please see these instructions.  

[wmh408]

Thanks for the reply. I double checked my form 8805, it says "Claim this amount as a credit against your US income tax" along with the withhold. So looks like this need to be added in Schedule 3, Line 13d, "Credits from form", and manually enter the form number, and amount. However I cannot find the option in Turbotax to do so. In section "Other Credits", it only lets me to pick from forms, 8689 or 8912. How do I manually add another form to Schedule 3 Line 13d?