You can't change the amounts on your W-2. Box 1 is your actual gross pay. Box 2 is the amount of tax that was actually withheld, right or wrong. You cannot calculate box 2 from box 1. Code DD in box 12 has nothing to do with your income or withholding. It's the total cost of your health insurance, and it's just for your information. It's just chance that box 1 minus the DD amount is approximately equal to box 2. You have to enter your W-2 as it is and pay the additional tax that you owe.
