iPad Air M2 doesnt show streaming apps on external display in full screen

I have Apple iPad M2 Air. I am trying to get the streaming apps like Amazon Prime and Netflix to display on External monitor connected via HDMI and Stage manager ON.

When I send the app to the external monitor and select ‘Enter full screen’, nothing happens. The app is displayed at the centre of the screen. This is true for Netflix, Prime and Sony LIV. For YouTube, this works fine.

How can I fix this? Such a weird behaviour for a basic thing as this. That too on an expensive iPad.