Deductions & credits

We did our refi in 2020.  The first loan was 366k.  We refinanced with the same lender and took cash out.  The new loan is 430k.  Do I still need to combine the 1098 forms?  If so...How do I combine box 2?  Do I add them together which would make my outstanding mortgage principal 796k?  That doesn't make sense to me...Or do I just put the 430k?  Very confusing...