Also upon adding my second newborn onto 2021 filing, the software did not calculate the $3600 which was not allocated as she was born in the year nor was there any info of it being owed eventually.
Before you entered the $1,800, the full child tax credit may have been on your tax return already. So, when you added the advance that you received, it reduced the amount owed you, so that may be why your refund went down. You may have to go back through your entries for setting up your second child to make sure you entered everything accurately. Here is information on what qualifications are needed for your child to allow you a child tax credit:
You can look at your form 1040, on lines 19 and 28 to see what your child tax credit is.
You can view your form 1040 while working in the online version of TurboTax by following these steps:
While working on your return in the Federal section of TurboTax:
1. Choose the Tax Tools icon on your left menu bar
2. Tools
3. View Tax Summary
4. Choose the Preview my 1040 on your left menu bar