Business & farm

Your employer did not correctly report you bonus. To report the bonus, you'll enter the income as additional wages that were not reported on a W-2. You will have to pay Social Security and Medicare taxes since the employer did not withhold them from your bonus. 

Per IRS, Publication 15, Page 15, 5. Wages and Other Compensation:

Wages subject to federal employment taxes generally include all pay you give to an employee for services performed. The pay may be in cash or in other forms. It includes salaries, vacation allowances, bonuses, commissions, and taxable fringe benefits.

To enter your bonus that you received on a 1099-NEC:

1. Sign into your TurboTax Account
2. Click on Pick up where you left off 
3. On the left side screen, select Federal then Wages & Income.
4. On the Wages & Income screen, scroll down to Less Common Income. Then scroll down to Miscellaneous Income, 1099-A, 1099-C and select Start/Revisit.
5. On the Let's Work on Any Miscellaneous Income screen, select Other income not already reported on a Form W-2 or Form 1099 (even though this was reported on a 1099-NEC) and Start
6. On the Other Wages Received screen, answer Yes and Continue
7. Continue through the interview until you get to the Any Other Earned Income screen and answer Yes and Continue. Ignore the note that says not to enter payments for which you will receive a 1099.
8.  On the Enter Source of Other Earned Income screen, select Employee compensation that was not reported on a W-2 and Continue. 
9. On the Employee Compensation Not Reported on a W-2 screen, click Continue
10. Continue with the onscreen interview until you get to the Report Your Wage Income screen and enter the information. For the Reason Code, select H - I received a Form W-2 and a separate Form 1099-MISC and/or 1099-NEC and the income should have been reported on Form W-2 then Continue 
11. On the Report as Wages screen select Done