I'm not sure what you mean by "not calculating." If you mean that the mortgage interest deduction does not appear on Schedule A at all, you might have answered a question incorrectly. When TurboTax asked whether the loan is secured by a property of yours, did you answer Yes? If the loan is not secured by a home that you own, the interest is not deductible. A mortgage loan is normally secured by the home that the loan was used to purchase.
