The SSN needs to be entered in the Personal Info tab and not in the W-2 section. Please take the steps below to make sure your Social Security Number is entered correctly.
1) Sign into TurboTax Online
2) Continue your return by click Taxes> Tax Timeline > Take me to my return.
3) Go back to the Personal Info tab and make sure your Social Security Number for you (and your spouse, if MFJ) are entered correctly.
Now you may have to Delete and Re-enter your W-2. To complete this follow the steps below.
1) Once confirmed, click the Federal Taxes tab.
2) Click Wage & Income (Wages & Expenses using Self-Employed)
3) Find Wage & Salaries, Form W-2 and click Start/Revisit.
4) The W-2's you've entered will be listed. Click the trashcan symbol to delete your W-2.
5) On that same page click +Add a W-2. Follow the prompts to enter your W-2.
If you have a 1099, you may have to delete and re-enter that as well.
Once you have completed this go back to your state return. If the changes do not reflect in your state return you may have to delete the state return and start it over again. Please see the following FAQ to delete your state return. https://ttlc.intuit.com/replies/3301384