This issue also existed last year. They told me to combine (in one line) both mortgages and the issue seemed to go away. Also, although the pop-up message mentions a lower amount of mortgage interest will be deducted, the final summary seemed to show everything so maybe it's just the pop-up message. First look at the final summary and see if the mortgage interest deduction reflects both homes. If not, combine both into one line for the amounts and interest and see if that fixes it. I also added a footnote into my return to include what I did, and mentioned it was a known TT defect. Regards!
