Turbotax no longer supports 2017 so you can't use it to amend the state return. It'll have to be done manually, if needed.
what the state is saying is that you had a balance due on your return that was not paid on or before the original due date (4/15/2018). This may have been shown on the return you filed or if showed a refund or $0, the state found errors that resulted in you owing. What I don't understand is why it took the state over 6 years to send you this. https://www.azleg.gov/ars/42/01104.htm
if you owed and paid, you'll have to send them proof of payment, along with the notice, which usually would be the front and back of check or copy of the bank statement. If the state changed the numbers, the notice should state how to respond if you disagree with the findings.