Always on display on iPhone 14 Pro

Hi! I'm facing a problem with my iPhone 14 pro. Although it may not be a problem at all. But so far for me it's a problem that I can't solve. The thing is. The "Always on Display" function can stop working on its own. Mostly it happens at night. All related functions that can affect this are disabled. (Power save mode, CarPlay, continuity function for the camera, focus modes I don't use) I can't figure anything out. It's just that when I lock the phone and put it down, after a while (30 seconds to a minute) the "Always on display" function turns off by itself. It started about a month ago, maybe more. before that it never happened.