The stimulus payments were for 2020 and 2021 only.
If your parents claimed you as their dependent, they would get your stimulus. Dependents were not eligible for stimulus payments.
If your parents filed a return and never received a stimulus, they can file amended returns to claim the missing amounts.
If they never filed a return, they will need to file a 2020 return to claim the first two stimulus payments and a 2021 return to claim the third payment.
It’s possible they never received a payment because they were not eligible. TurboTax will tell them when they either file or amend their return.
To file prior year returns, buy the prior year programs and install them on your computer.
Go to File your 2021 taxes and File your 2020 taxes.
If you used TurboTax in 2020 and/or 2021 you can amend your return for free.
See: How do I amend my federal tax return?
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