why did Turbo tax prepared an estimate California state tax 2020 for me when I am getting a 2019 state refund?

Due to a status change in 2018, I ended up owing  California state tax in 2018, in addition, Turbo tax prepared and instructed me to pay Estimate  State tax in 2019.   In mid -2019, I updated my filing state status in  state filing , had taxes withheld thru payroll, paid all estimate state tax. I just filed my 2019 returns, i got a refund on State (I guess with all the payroll deduction plus estimate taxes I paid, I actually overpaid, hence getting a refund), but Turbo again prepared an Estimate State tax for 2020? I am confused, why do i have to pay estimate tax for 2020 when i am getting a refund for 2019 now? 

Can i ignore the estimate tax if i believe my payroll deductions should cover my annual tax due?

Thanks for all your help.