here is how the Stimulus REALLY works (Assuming your income is below the limit established for stimulus)
The way this REALLY works is EVERYTHING is based on you 2020 income, filing status and number of children under the age of 17 on your 2020 tax return. (this is why TT is excluding your 17 year old). What these numbers were in 2018 and 2019 does not matter.
The IRS will calculate your stimulus based on 2020 numbers; that is what is considered the ACTUAL.
The two payments were just ESTIMATES; the 1st stimulus was an estimate based on either the 2018 or 2019 tax return, using whatever was available.. the 2nd stimulus was an estimate based on the 2019 tax return only..(Your son was under 17 in 2018 and 2019, so he was including in the ESTIMATED PAYMENT)
if the ACTUAL is greater than the ESTIMATE, you will receive that amount as a credit on your 2020 tax return.
if the ESTIMATE is greater than the ACTUAL, you are not required to return the money nor does it impact your refund - you received what the law allowed. Line 30 on Form 1040 will be zero.
does that help? if you go through the math of your situation against my explanation above, you'll understand why Line 30 is correct. If you believe it is still not correct, state the following and I will explain with your numbers
1) are you filing joint or single
2) the number of children under the age of 17 at a) 12/31/18, b) 12/31/19, c) 12/31/20
3) the amount of your a) first stimulus payment b) second stimulus payment)
