There are two issues with the software when it comes to reporting 1098 refinancing.
Presuming that your original loan pre-date 2017 and you refinanced your mortgage last year - without pull out additional money.
1. The first problem is that the software may add up the mortgage principle from both 1098. For example, let say your original principal is 910k and your new one is 900k. The system will take it as 1,800k which is well over the 1 mill you are grandfather in. It looks like they recently fix this but you will have to double-check.
2. The Second issue is that the software does not account for your original loan that predates the 2017 - 750k limitation so you only get the deduction up to 750 and not 900. Your original loan means that you are grandfather in for up to 1 million deductions vs 750k --- this is pro-rated though.
Turbotax WORKAROUND: https://ttlc.intuit.com/community/loans/help/what-do-i-do-if-i-have-multiple-1098s-from-refinancing-...
