Mortgage Interest Not Included in Itemized Deduction

[tunamochi]

Hello, I'm filing 2021 Tax. I have a max state/local tax deduction of $10,000. In addition, the total mortgage interest is $18,424 and our original loan is less than $750K (refinanced in 2021). So I thought we can go with an itemized deduction of $28,424 but Turbo Tax insists, if itemized, the deduction is only $10,000 for the state/local tax. I'm not sure what I am doing wrong? 

[rjs]

There are lots of things you could have done wrong. One common error is to not correctly answer the question about whether the loan is secured by a property of yours. If the loan is not secured by a property that you own, the interest is not deductible. Most mortgage loans are secured by the property that the mortgage is for.