It says my taxes got rejected because my dependents ssn is on another tax form like someone else claimed them, but nobody else has. What do I do?

If your return was rejected due to your dependent's SSN being used on another return, the first thing to do is to verify that you entered the SSN correctly in the return. If it is incorrect, fix it and resubmit it. If it is incorrect, that means that someone did indeed use your dependent's SSN on a return. The IRS typically grants the tax benefit(s) related to dependents to the first taxpayer to file a return. It is not uncommon for a parent who qualifies to claim the child to have their e-file rejected because the child was already claimed by another taxpayer. If you qualify to claim the child under the law, file a paper return and claim the child as a dependent. This will start action on the part of the IRS to determine who actually qualifies to claim the child. You will receive mail from the IRS when they start this process. 

Nobody else has that you know of.

You are forced to file a paper tax return via US Mail.

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