If you did not report your 1099-MISC, you should file an amended return to report it. If you file the amended return and pay any tax due by April 15, 2019, there will be no penalty at all. If you pay after that date, you will have to pay interest on the tax due.
Please see the
following TurboTax FAQ for
instructions on how to amend your tax return in TurboTax.
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