TT is counting my retirement and social security income as part of AGI and not allowing me to claim the EIC when my actual earned income is $20,000.

Were you 66 years old as of 12/31/17?

AGI plays a part in EIC as well.

I was more than 66 years old on 12/31/17.

Sorry--you cannot get EIC if you are 65 or over.  Furthermore, even you only "earned" $20,000, the other income like retirement and SS counts.

You are above the age limit to receive the Earned Income Credit.  Even if you were young enough to qualify, both your AGI and your earned income must be below the limits,not just earned income.

We have a qualifying child so I don't know if the age limit applies, but I hadn't seen the inclusion of AGI, so in any case we do not qualify.  Thanks.