Assuming this question is found under OTHER Income Taxes Paid in 2018, then if you didn't get a state tax refund last year, you put the amount you owed/paid here.
For fields that need to be filled in, TT labels estimated state taxes "estimated state taxes" The 1st section is Estimated Tax Payments, 2017 state estimated taxes paid in 2018 (due Jan).
BTW, TT prefills both answers for me since I have used them before.
