You must have entered something that indicated that the mortgage interest is not deductible, or you answered a question incorrectly.
Go through the mortgage interest questions again. Does TurboTax ask whether the loan is secured by a property of yours? If it asked that question, did you answer Yes? If the mortgage loan is not secured by a property that you own, the interest is not deductible. Most mortgage loans are secured. If box 7 on the Form 1098 is checked, or there is an address in box 8, the loan is secured.
When TurboTax asked whether this is the original loan that you used to buy the home, did you answer Yes? If it's not the original loan that you used to buy the home, post the details about the loan.
