It is possible to accidentally indicate to TurboTax that you have an HSA when you don't.
To remove all data associated with the HSA and form 8889, 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
*** Desktop***
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.
*** Online ***
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
6. continue with your return.
If at any point you see a question that asks you "What type of High Deductible Health Plan (HDHP) did [name] have on December 1, 2017?" (yes, 2017), just enter "None". This question does not apply to you.