@Jacksonville You put all kinds of personal information here in a public internet forum where it can be seen by anyone. No one in this forum can do anything about your ex or his attempts to claim the children. We cannot "block" him for you.
If you are the custodial parent of the children then if he files a return and claims them, you can file your own tax return that claims the children and file it by mail. Then the IRS will sort it out and he will face repayment of any refund he received etc. If your 2021 e-file is rejected then file by mail.
https://ttlc.intuit.com/questions/1900655-what-to-do-if-you-suspect-tax-related-identity-theft
Most important) Follow the IRS procedures for reporting a fraudulent return, documented here: www.irs.gov/uac/Taxpayer-Guide-to-Identity-Theft
IRS INFORMATION REFERRAL TO REPORT VIOLATION OF TAX LAW
https://www.irs.gov/pub/irs-pdf/f3949a.pdf
If your Social Security number is compromised and you know or suspect you are a victim of tax-related identity theft, take these additional steps:
- Respond immediately to any IRS notice; call the number provided.
- Complete IRS Form 14039, Identity Theft Affidavit. Then print and mail or fax according to the instructions.
- Continue to pay your taxes and file your tax return, even if you must do so by paper.
6-digit IP NUMBER FROM IRS
https://content.govdelivery.com/accounts/USIRS/bulletins/2af48f0?reqfrom=share
**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.**
