Please see this information from the Help article.
Can I include education expenses on my 2019 return that I paid in 2018 or earlier?
You can't include expenses you paid in 2018 (or earlier) on this year’s 2019 tax return. If you forgot to include them, you'll need to amend your prior-year return to claim those expenses.
Likewise, if you paid tuition in 2019 for the 2020 school year and the classes begin in the first three months of 2020, you’ll include them on your 2019 tax return.
