https://ttlc.intuit.com/questions/1900655-what-to-do-if-you-suspect-tax-related-identity-theft
Sorry your ex-BF is putting you through this. Unfortunately, if he e-filed a tax return claiming you or your son as dependents and the IRS accepted his return, neither you nor your son will be able to e-file your own tax returns this year. You will have to print, sign and mail your own tax returns that are prepared correctly. The IRS will process your returns--although mailed returns are taking much longer right now-- and the IRS will sort out the issue of the two of you being claimed fraudulently.
Hope you are able to pursue him for the back rent--unfortunately, TurboTax cannot help in any way with that sort of issue. Good luck. Stay safe.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
