You claim your children as dependents, as you should, and your return is rejected. This could be because somebody else has stolen your children's Social Security numbers and fraudulently claimed your children as dependents to inflate their own refund.
Where to turn for help if you believe you are a victim of tax identity theft:
The Internal Revenue Service now has a designated group that responds to citizens' concerns about Tax ID theft. You can contact the IRS Identity Protection Specialized Unit at (800) 908-4490
If the IRS itself is not responsive to your tax identity theft complaint, you may be able to get assistance from the Taxpayer Advocate Service. Call 1-877-777-4778 to see if you are eligible.
The Federal Trade Commission is the nation's consumer watchdog and the designated repository of all identity theft complaints. Therefore, you should also file a complaint with the FTC.