Making a wild guess here based on no facts, that this has something to do with your state return for the state of Michigan? There's 36 other possible states. But I"ll go with MI for now. Fill out the form as instructed and mail it back. You have 30 days. After that it's to late.
The Income Allocation for Non-Obligated Spouse form (743) is automatically generated for mailing to taxpayers when one person on a jointly filed return is potentially liable for a debt. ... Failure to file the completed form within 30 days will result in the entire refund, if needed, being applied to the debt.
For more information see https://www.michigan.gov/taxes/0,4676,7-238-75545_43715-168410--,00.html
