Recovery Rebate Credit Worksheet changes my refund amount

If we aren't supposed to be taxed on our stimulus checks, why does my state refund go down when I input my first stimulus payment in TurboTax Home Business 2020? On line 16 I enter 3,400 and my Oregon State refund drops. Nothing changes when I enter anything on line 19, regardless of how much I input. Any help with this would be greatly appreciated, as I think I am ready to file other than this. If I'm mistaken, please point me in the direction as to why this would affect my refund.