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In order to correct the error, reference the DataValue (this indicates what person or number the rejection is related to). For more information, regarding how to view the details and data values related to rejections and refusals reference Viewing Reject and Refusals.
Possible Causes:
The dependent filed their tax return in the same calendar year, and did not designate themselves as a dependent on another individual's tax return.
Someone else has used the dependents social security number and information to file a return, either fraudulently or in error.
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