You haven't taken into account those people who did not receive the second stimulus. You are required to fill out the federal Rebate worksheet, right? You are required to enter how much you received for each stimulus. Let's say you received zero for the second stimulus and you enter "0" on the rebate worksheet. Now go to the Oregon return. Oregon has subtracted the amount you received as a credit on your federal worksheet for that second stimulus. So if you are single and you are due $600, then the program calculates a $600 subtraction for that second stimulus on your 2020 Oregon tax return, EVEN THOUGH YOU HAVEN'T RECEIVED THE MONEY YET.