How to keep my Android phone asleep until I press the power button

When I am done with doing something on my Android phone, I put it asleep with the Power Button. I expect it to stay asleep until I press Power again, or perhaps until a phone call comes in. This is to minimize draining the battery. However, the phone wakes up when putting it away, e.g. in my trouser bag. After several seconds the screen goes dark again. But why? Is this a 'feature'? When walking in the dark, the phone backlight will shine through my clothes. Is it possible to turn this 'feature' off? I might be old fashioned, wanting to be in control in turning this thing on and off when I, the owner, want this. This behaviour happened with my previous phone, Motorola Moto, with android 11, and with my current Moto E32s with Android 12.