i answered yes for eic dissalowance because several years back i had went to liberty tax and the amount they told me i would be getting back ended up being significantly reduced by about half so i was confused and answered the question incorrectly

Follow these steps to add Form 8862 to your taxes.

1. Sign in to your TurboTax account and click Continue your return.
2. Click Search in the upper right-hand corner and search for 8862.
3. Select the first result: Jump to 8862.

Now you are at the beginning of the Earned Income Credit.

1. Continue on the first two screens and stop when you see Do any of these uncommon situations apply?
2. Check the box that says, I got an IRS notice saying that I can only claim the Earned Income Credit if I file an 8862 and Continue.  
3. Select Done, but hang on, there are a few more steps to go. 
4. Answer the question about your IRS notice.

Does this mean I should've previously received a letter in the mail from the IRS? My taxes were rejected with this same code, but I'm not sure why I need to attach a form when I've been doing without on previous years. This is the first time in 30+ years that my taxes were rejected.

Not necessarily.   If you checked the wrong box in the Earned Income Section, you would receive that rejection notice.  You can go back into the return, go back through the Earned Income Credit questions and attach Form 8862 if required.    Then resubmit the return for e-filing again.   @Sonnymaha

THANKS 

What if I don't know or remember if there was a letter sent out? How do I find out? IRS keeps sending me to accounting and they are too busy and it just hangs up. 

@sakeman55

Please see this Help Article to assist with this particular code so you are able to file your return.  To confirm, you would still need to get this information from the IRS.  Please see below how to reach out to them directly:

To call the IRS: 800-829-1040  hours 7 AM - 7 PM local time Mon-Fri

• Listen to each menu before making the selection.
• First choose your language. Press 1 for English.
• Then do NOT choose the first choice re: "Refund", or it will send you to an automated phone line.
• Instead, press 2 for "personal income tax".
• Then press 1 for "form, tax history, or payment".  
• Then press 3 "for all other questions."
• Then press 2 "for all other questions."  It should then transfer you to an agent.

It's that everytime I submit my taxes this code keeps coming up.

For Rejected returns with this code, please see the Help Article here to assist you with correcting and resubmitting your return.