Galaxy Fold does not support 'Full screen' only for my app

Hi. I’m an android application developer.

From one day, my app does not appear in full screen mode on the Galaxy Fold. But before, it was clearly seen in full screen mode.

That’s really weird because I have not modified any features in the app. When I switch it to ‘Full screen’ in Full screen apps(Settings-Display), it continues to go back to ‘Auto’. Also, I can no longer see ‘Change app aspect ratio’ button of the app in the state of clicking the recent button only for my app.

My app keeps full screen very well when I run with Android Studio’s emulator foldable, but the problem occurs only running with the Galaxy Fold.

Does anyone know how to solve the problem?

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