Amended Tax Return for 2019

I discovered I omitted a  form1099 from a broker.  Originally I had a return that I partially credited to 2020 taxes.  The return was $3,000.  I credited  $2,000 to 2020 taxes and got a check for $1,000.  The original tax return was accepted and the check was deposited.  Now because of the error I owe about $500.   It seems to me that then I would either send $500 to the IRS and my credit for my 2020 taxes would stay at $2,000 or my credit for 2020 taxes would be $1,500 and I would send nothing right now with my amended return

The way I complete Turbo Tax it says that I both owe a $500 check and that my return is $1,500.  Could you tell me what I'm doing incorrectly?

 

On 1040X line 16 - if I am sending $500 should I enter it there?  Turbo tax doesn't show me how to do that unless I simply override the line on the form.