So with the stimulus checks going out again I have an issue. My parents did not claim me as a dependent but the IRS claims that I have a box checked on my taxes that says I can be claimed as a depende

Forget about your 2019 tax return and the stimulus.   Pay attention to what you check -- or do not check -- when you prepare your 2020 tax return.

The stimulus check is an advance on a credit you can receive on your 2020 tax return.  If something went wrong or you did not get the stimulus check this year, you can get it when you file your 2020 return in early 2021—if you are eligible.It will end up on line 30 of your 2020 Form 1040.

https://www.irs.gov/newsroom/economic-impact-payment-information-center-topic-j-reconciling-on-your-2020-tax-return

https://www.irs.gov/coronavirus/coronavirus-tax-relief-and-economic-impact-payments-for-individuals-and-families

https://ttlc.intuit.com/community/tax-topics/help/how-will-the-stimulus-package-impact-me/00/1393859

don't worry about what occurred in the past. 

What is critical is how you fill out your 2020 tax return.

CAN your parents claim you? if they CAN, whether they did or not, you are not eligible for the stimulus.

But if they CAN'T claim you, the 2020 tax return will act as a reconciliation of what you are due.  the money will appear on Line 30 for Form 1040 if you are eligible.

Please read this link which explains who can claim who and why. 

https://turbotax.intuit.com/tax-tips/family/rules-for-claiming-a-dependent-on-your-tax-return/L8LODbx94