I successfully entered Q1, Q2, Q3 estimated tax paid in 2019 Turbo Tax Deluxe.   But it will NOT allow me to enter Q4 estimated tax paid.  I tried changing the payment date without success.  I spent a hour on-line with Turbo Tax agent without getting an answer.  I uninstalled my TT2019 Deluxe then downloaded/re-installed without success.   There is no other apparent problem in TT2019 nor in any other application on my computer.  

What must I do to enter my Q4 estimated tax in TT2019 Deluxe?