No, it was not a TurboTax problem. It was the Congress who passed the legislation authorizing the deduction for Mortgage Insurance well after the start of the 2017 tax filing season.
There should be a phone number on the letter you received to contact TurboTax for any questions and assistance in amending the 2017 tax return. Amending your 2017 tax return to add the Mortgage Insurance would only be necessary of you itemized your deductions using Schedule A or the that the MI would increase your itemized deduction to be greater than your standard deduction for your filing status.
Or contact TurboTax support for assistance using their contact website.
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