I'm having the same problem. Like flandar, I have three 1098s -- the original lender, the lender to which the loan was transferred, and the lender that refinanced the loan. Because the last loan was a refinance, it should use the same home acquisition debt as the prior loan (so I am not subject to the $750,000 limit). I had to manually adjust the federal form to fix it so it would limit the deduction. (The instructions for that worksheet were useless and contained no discussion or boxes to reflect refinances of pre-2017 limits.)
Now the California form wants to adjust for interest and points reported on form 1098 by -$12,557, which would increase my state tax by nearly $1,200. There is no explanation for how that figure is calculated. When I click on the link for "Why would I adjust my mortgage interest," I get a pop-up that tells me only that California does not subscribe to the federal $750,000. But that difference, if applicable (which it is not), would increase my the deductible state interest, not reduce it like the software is doing.
I agree that this is a very serious error.
