Why did the taxpayer receive Michigan Department of Treasury letter C-4364 regarding an adjustment to their return?
According to the text of the letter:
Your claimed subtraction of military retirement benefits due to service in the U.S. Armed Forces or Michigan National Guard, or taxable railroad retirement benefits on your Michigan Schedule 1 was disallowed. Based on the information you provided you may be eligible to claim a deduction by completing Michigan Pension Schedule, Form 4884 for this subtraction.
This adjustment is based on an amount that has been claimed on MI Schedule 1, line 11.
The MI Department of Treasury has advised Drake that the taxpayer should mail a copy of the letter and copies of any supporting documentation, such as the 1099-R or 1099-RRBs, supporting the amount claimed on MI Schedule 1 line 11, to the address listed in the letter. This should be enough documentation needed for them to reconsider the adjustment that they have made.