Just because your parent's are not claiming you as a dependent does not mean that you cannot be claimed as a dependent. If they can claim you as a dependent then you do not amend your 2023 tax return.
If you are age 19 or older and a full time student under the age of 24 they probably could claim you as a dependent under the Qualifying Child rules.
However, if you are age 19 or older and Not a full time student and your gross income in 2023 was $4,700 or more then no one can claim you as a dependent.
What is your status?
To be a Qualifying Child -
1. The child must be your son, daughter, stepchild, foster child, brother, sister, half brother, half sister, stepbrother, stepsister, or a descendant of any of them.
2. The child must be (a) under age 19 at the end of the year, (b) under age 24 at the end of the year and a full-time student or (c) any age and permanently and totally disabled.
3. The child must have lived with you for more than half of the year. Temporary absences while away at college are considered living with you.
4. The child must not have provided more than half of his or her own support for the year.
5. If the child meets the rules to be a qualifying child of more than one person, you must be the person entitled to claim the child as a qualifying child.
6. The child must be a U.S. citizen or U.S., Canada or Mexico resident for some portion of the year.
7. The child must be younger than you unless disabled.
