Deductions & credits

I've thought they were wrong all along but apparently for the wrong reason...but I'm clueless about what I need to ask for from them.  There was a balance that was cleared in 12/2019 so there was zero owed Jan. 1, 2020, but the HELOC had been active since it was established in 2018 and was drawn from again on 1/6/2020 and that balance continued through 2020 which is the source of the interest paid for the year.