The deduction for PMI expired at the end of 2017 and as of this date Congress has not renewed the deduction for tax year 2018.
See IRS Schedule A Itemized
Deductions instructions on the first page - https://www.irs.gov/pub/irs-pdf/i1040sca.pdf
Expired deduction for mortgage insurance premiums
. At the time these
instructions went to print, the deduction
for mortgage insurance premiums had
expired. You can't claim a deduction for
amounts paid or accrued after 2017.