The amount of excess premium tax credit repayment, calculated on line 29 of Federal Form 8962 Premium Tax Credit (PTC), has a different calculation if there was a self-employed health insurance deduction claimed on line 16 of Schedule 1 (Form 1040).
Per the IRS instructions for Form 8962, p. 15:
If you are self-employed and are claiming the self-employed health insurance deduction, see Self-Employed Health Insurance Deduction and PTC in Pub. 974 for the amount to enter on line 28.
The instructions for calculating the self-employed health insurance deduction are explained in IRS Publication 974 Premium Tax Credit (PTC), starting on page 56. To review the worksheets in TaxAct that reflect those calculations, see the navigation instructions below. On Worksheet X (as explained in the publication) there is a calculation on line 25 of Part III: Repayment Limitation that reflects the amount that must be repaid.
To review the worksheets that perform the calculation of the repayment limitation, follow these steps:
Note: If you see a message indicating you have not paid your return fees, click the View/Pay link, which will direct you through the Paper Filing steps. Continue through the screens until you have processed the payment for your product fees and then repeat the steps to print.