As you probably know, code DD is the amount that your employer and you contribute to your health insurance premiums. You are correct that this has nothing to do with an HSA (other than to have an HSA the health insurance must be a High Deductible Health Plan (HDHP)).
The code DD amount should not appear in the HSA interview nor on your form 8889.
Did you import your W-2? That is, did you enter your employer's EIN and have TurboTax fill in the W-2 fields for you?
If so, the import process occasionally fails, probably because the employer built the W-2 data packet incorrectly.
If you imported your W-2, I encourage you to do the following:
1. copy down your W-2 information (if you don't have a printed copy)
2. delete your W-2 (look for the trash can icon to the right)
3. enter your W-2 information by hand, that is, skip the screen that asks for your employer's EIN, and go to the next screen and enter all fields manually.
If you did not import your W-2 but the code DD is showing up in the HSA interview or on form 8889, I would encourage you to delete your HSA data.
The safest - although brute force - way to fix this is to do the following in this order:
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. go back and
redo the entire HSA interview (if you have an HSA) or just continue with your return.
