Form 8862 should be completed when one of these credits (Earned Income Credit (EIC), Child Tax Credit (CTC), Additional Child Tax Credit (ACTC), Credit for Other Dependents (COD), or American Opportunity Credit (AOC)) were disallowed in a prior year return for anything other than a math or clerical error.
You didn't share the reject code, but if it's for a missing Form 8862, you can add the form to your tax return. Refer to the TurboTax Help article What is e-file reject F1040-164-01? for instructions.