"Always On" display won’t turn off on my iPhone

Hello. After turning on AoD, I wanted to check if it turns off automatically to preserve battery life, but it doesn’t seem to ever turn off. I’ve tried seeing if AoD turns off automatically when I put my phone in my pocket, but I can still see that AoD stays on in my pocket even after a couple of minutes. Same thing happen when I put my phone face down on my desk, I’ve tried putting it on edge of my desk tiny bit of my screen is visible, but camera and light sensor is covered, but it stays on. Why is that?

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