I am seeing the same issue with the TT software. My mortgage was about $800k taken in mid-2017. I refinanced in Oct. 2019 and TT is calculating the average mortgage for 2019 as $1.3M. As others have pointed out, it is not taking the refinance dates while calculating the average mortgage for the year. It seems to (erroneously) think that I had both the mortgages for the entire year.
