According to the forms availability table for Michigan, Form 4884 is available. Are you using TurboTax Online or TurboTax Desktop (CD/Download)?
If you are using TurboTax Desktop, be sure your software is updated. To do that, see the instructions I'm linking below.
How do I update TurboTax CD/Download?
*** I am NOT a tax expert. I am a seasoned TurboTax user, and volunteer to provide assistance to TT users. Nothing I post is to be considered TAX ADVICE; I bear no legal liability for responses.***
