If you have already filed, you might not be able to go back to add. You can return to the program to make corrections without amending only if your return is being rejected. If your return is accepted, to add information, you will have to amend it. You cannot just go back to edit.
If your return got rejected for any reason, you can return to the program to add your dependent along with other changes and re-submit it. For instructions, click here Fix a reject 2019. You do not need to file an amendment 1040-X.
If your return has been accepted, you will have to amend by filing a Form 1040-X. Click here for instructions Amend 2019. Please note that you should not try to amend your return until it has been fully processed and you have received your refund or your payment has cleared. If by editing the information does not change the refund or amount you owe, you do not need to submit the amendment.
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