American Opportunity tax credit

On my 2019 tax return our son was eligible for the Am Op credit. Child #1 was in the third year of college and had tuition + books. This year child #1 finished ( had 4 year of Am OP : 2016, 2017, 2018, 2019) but still had expenses.  Child #2 started college with expenses and had never used the Am op credit.

 

When I entered all the 1098T's TurboTax told me I we were not eligible for credit. Our income is $149,000 with three dependents. Last year we were 132,732 with three dependents. Why are we no  longer eligible?

Thanks-
Celeste