If someone is using your social security number what you do, report the fraud as soon as possible.  Your tax refund is probably in jeopardy!

Reporting  Tax  Fraud to the Internal Revenue Service:

What can you do if I think someone has filed a tax return using my social security number?

Answer:

The IRS has security measures in place to verify the accuracy of tax returns and the validity of social security numbers submitted.

If you receive a notice from the IRS that leads you to believe someone may have used your social security number fraudulently, please notify the IRS immediately by responding to the name and number printed on the notice or letter.

You can contact the Federal Trade Commission (FTC) Identity Theft Hotline toll-free at 877-438-4338 if you suspect someone else is using your social security number, or to secure information on how to prevent identity theft.

If you are an actual or potential victim of identity theft and would like the IRS to mark your account to identify any questionable activity, please complete Form 14039 Identify Theft Affidavit available on irs.gov.