I have a 15 year mortgage, 1st payment was 12/1/20. My maturity date is 11/1/35. everything is entered correctly in the terms section yet Quicken believes my payoff date is 9/1/35. the payment schedule is also incorrect as the interest portion should be goi ng down as the principle goes up. There are months where the interest goes down and then up and then down, same with the principal. What am I doing wrong?