Help. Turbo tax is reflecting a mortgage interest deduction in the final review that is less than the amount paid. Primary home, 576k, no special factors.

It's clear-cut--interest on 1098s add up to amt shown in that section of TurboTax. But in the review, Turbotax tells me that the deduction is 8000 less than the amount paid. Checked IRS guidelines several times and it is all deductible. How can I correct it?