When reviewing how the tax already paid was caculated, it included another amount and describes it as "other tax payments you made throughout the year"

If you did not pay estimated taxes, the tax paid throughout the year could be the additional Medicare tax of 0.9% withheld on earnings over $200,000 for the year.

No income above $200,000. Refund in 2020. Only taxes withheld were through employer

Preview your 1040. The Tax Smart Worksheet and line item 16 show tax amounts that are reflected on you income tax return. 

• Please see the instructions to Preview your 1040.