I got the Economic Impact Payment form after my tax returns were accepted, how can I add the information to the Recovery Rebate Credit on the amended tax return?

I tried to add the information from the Economic Impact Payment on the amended tax return form, but I can find where to put the information. I could not find where anything mentioned the Recovery Rebate Credit nor the Economic Impact Payment. My tax returns have already been accepted and I got my returns back, but I want to update my document still.