Did you have an HSA (Health Savings Account)? If you have a code W in box 12 of your W-2, then your employer thinks you had an HSA.
Did you have HDHP coverage (High Deductible Health Plan)? Your employer can tell you if you did.
Did you receive a form 1099-SA or a 5498-SA in the mail? These are also signs that you have an HSA.
If you had an HSA in 2017, then you need to complete the HSA interview, at Federal->Deductions & Credits->Medical->HSA MSA Contributions. Be sure to go all the way to the end, until you are returned to the Deductions & Credits menu labeled "Your Tax Breaks".
If none of the things above apply to you, then you likely answered a question in such a way as to make TurboTax think that you had an HSA (and thus triggered the 8889) when you don't.
To fix this, please do the following:
1. make a copy of your W-2(s) (if you don't have the paper copies)
2. delete your W-2(s) (use the garbage can icon next to the W-2(s) on the Income screen
3. go to View (at the top), choose Forms, and select the desired form. Note the Delete Form button at the bottom of the screen.
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3. go to Tax Tools (on the left), and navigate to Tools->Delete a form
4. delete form(s) 1099-SA (if one), 8889-T, and 8889-S (if one)
5. go back and re-add your W-2(s), preferably adding them manually
Continue with your return. If you see the question, "What type of High Deductible Health Plan did [name] have on December 1, 2016?", be sure to answer "NONE".