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Possible Cause 1: The taxpayer has an IP PIN and it is not included on the return.
Resolution: Enter the taxpayer's IP PIN on the tax return.
If the taxpayer can not obtain their IP Pin then their return must be paper filed.
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Possible Cause 2: The taxpayer's information is entered incorrectly and the IRS system thinks it is a different person (double-check the SSN, name, and birthday).
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