How to do this? Employer overpaid in 2019. I repaid in 2020. W2c covers SS & FICA. They state: Report credit on 12d, Sched 3 of 2020 return. Label: IRC1341 on the entry.

So my employer overpaid at the end of 2019 - they made me repay the overpay amount + federal income tax  that they sent to the IRS . the W2c they sent only adjusted SS tax and FICA. They di NOT reduce the amount of income on my 2020 w2 at all. Thus, they have told me to do this: "The credit is reported on line 12d, Schedule 3 of your 2020 tax return. You should label this “I.R.C 1341” on the entry line. See the highlighted section of the attached draft 1040 instructions on page 102. You should be able to do this in Turbotax." I have done multiple searches and can not figure out how to accomplish this in Turbotax. Please help.