The Tuition and Fees Deduction lowers your Taxable Income on Form 1040.
The deduction shows on Schedule 1, Line 34.
However, some states start their calculation with the Federal AGI amount, which already includes the Tuition & Fees Deduction.
Michigan appears to do this on their Form MI-1040, but It looks like the Adjustment from Schedule 1 would go on the Michigan Form MI-1040 on Line 13 and is subtracted back out.
Since you are using TurboTax Desktop to Amend your 2018 return, you could enter the amount yourself directly on the Michigan form.
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