TurboTax offers free products for active duty "Enlisted" personnel. In the "My Info" section "Edit" your information. Verify/indicate you are "Military" and "Active Duty." Enter your rank from the dropdown menu.
In the "Wages and Income" section enter/edit you military W2. After entering the form information select "Active Duty Military Pay" on the "Uncommon Situations" page.
Complete the remaining interviews and your discount will be applied at checkout.