Another possibility, that could also cause the UT on Schedule 2 line 8c, is that you mistakenly entered code A or B in box 12 instead of the actual code from the W-2. Sometimes people see the box number 12a and think that the "a" is the code, so they enter code A, or the same for box 12b and code B. The lower-case a or b after the 12 is part of the box number, not the code. Codes A and B in box 12 are for Social Security and Medicare taxes on tips, if the employer was unable to withhold those taxes. If you did not get tips, you should not have code A or B in box 12. If you mistakenly entered code A or B in box 12, you can eliminate the need for Schedule 2 by entering the correct code.
