We cannot tell you specifically what to look at since we do not know anything about what you entered on those returns. We do not know what changed from 2019 to 2020----your filing status, number of dependents, credits, deductions, etc. so look at those. And look to see if your 2020 Form 1040 has anything on line 30---if so that credit reduced the tax you owed for 2020.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**
