I was not aware this advanced tax credit was to be paid back. If my AGI last year was under 100k and this year is actually a bit less as my wife wasn't working, why is my refund now in the negative and I owe money because of the Advanced Child Credit form 6419 letter?
It is not necessarily an error. It sounds like you are under the amount of income that would force you to repay your advance child tax credit. However, when you prepared your tax return in TurboTax, your full child tax credit was already included in your refund or tax due before you entered the amount of your advance child tax credit payment. So, when you entered your payment, it increased the amount of tax you owe or reduced your refund.
You can look on your tax return form 1040 on line 19 and/or 28 to see if you are receiving the proper child tax credit. If you are paying back any advance child tax credit, it would show on line 19 of Schedule 2 of your form1040.
You can view your form 1040 and primary schedules 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