How can i see the tax amount change at the top after adding new income/deductions like in the past?

Is there a > symbol at the top left where the refund monitor should be? If so, click that > symbol and the refund monitor should then appear.

Do you have "RaceMode" at the top where the refund monitor should be? Click the toggle next to RaceMode, or click Review on the right, to get rid of RaceMode and see the refund monitor.