Amended 2018 VA State Amount Owed Subtracts Previous Posted Return

Amending 2018 Fed and VA returns with 1099-B gains.  The Fed 1040X show the correct amount owed in line 20 as the difference of total owed on 1040 line 20 minus amount paid on original April 2019 file.

 

The amended state form VA  760CG shows amount owed as the difference of payment due and the amount already returned and deposited in my bank (2018 return of $419 subtracted from $495 amended due reported as 76 amount due on page 1 of 2). 

 

Why would the Fed 1040X account for correct amended amount due and not the state?  Further, can the state amended return be corrected in TurboTax to account for the 2018 $419  return already posted? Or do I need to manually print and fill the VA form to show the correct $495 amount due? 

 

Thanks for any direction you can provide.