It might be worth reviewing the 2018 versions of IRS Form 8801 and Instructions.
“Complete Form 8801 if you are an individual, estate, or trust that for 2017 had:
1. An AMT liability and adjustments or preferences other than exclusion items,
2. A credit carryforward to 2018 (on 2017 Form 8801, line 26), or
3. An unallowed qualified electric vehicle credit (see the instructions for line 20).
File Form 8801 only if line 21 is more than zero.”