Stay Cover Display for Every State in Galaxy Fold

Hello, i’m trying to adjust my apps for foldable devices (in this care Galaxy Z Fold 3). The application I made doesn’t want to fill the entire screen even tho the screen is unfolded, just a View in the middle with a background. Currently, my application runs perfectly only if when it is first opened from the cover display then when it switches to the main display it will be positioned in the middle as expected. Otherwise, if I first open the application while it is on the main display, the application will fill the screen and when I fold the phone to the cover display the application will be cut off. What should i do?

Have you ensured the check points mentioned in their website?
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