In the section for reporting gambling winnings, after entering the W-2G's that you received you will be asked if you received any other winnings, there you can enter the winnings reported on the 1099-K.
To enter, edit or delete Gambling Winnings and Losses -
Click on Federal Taxes (Personal using Home and Business)
Click on Wages and Income (Personal Income using Home and Business)
Click on I'll choose what I work on (if shown)
Scroll down to Less Common Income
On Gambling Winnings, click the start or update button
Or enter w2g in the Search box in the upper right of the program screen. Click on Jump to w2g
