My tax return was rejected because I know she put my SSN and claimed me as a dependent. I don’t know what to do. I also did not attend school full time last year.
You would need to talk to your mother. Either she or you need to amend the tax return. If your mom insists to claim you, you would need to amend your return by selecting "Someone can claim me on their return". If your mom changes her mind, she would need to amend to remove you, then you can re-submit yours later.
To amend, here is the information:
If you have already filed, you might not be able to go back to change. You can return to the program to make corrections without amending only if your return is being rejected. If your return is accepted, to change your 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 edit the information 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.