Turbotax for Mac not reducing mortgage interest deduction for loans totaling over $750,000

I have an issue that appears related to the mortgage interest deduction problems that others are reporting with multiple 1098s. I have a primary mortgage on my home that was issued prior to 2017. I also have home equity loan that was issued this year to renovate our master bath. The total sum of the two loans exceeds the $750,000 mortgage interest limit. Turbotax is erroneously telling me that I can deduct the full combined interest amount. It also is not allowing me to enter the average balance of each loan  (which is lower than the principal amount on the 1098). I've tried to change the numbers on the worksheet, but it won't let me change anything. Is this a known issue? Is there any workaround? I can't be the only one experiencing this problem.