You may have to contact the IRS and obtain an identity protection pin, so no one can file your return without that pin . Look at this article for more details on how to report this and how to get a pin for the future. The IRS will mail you a new Pin every year so you can file your return. https://www.irs.gov/site-index-search?search=identity+protection+pin&field_pup_historical_1=1&field_...
