iOS 11.2.1 Auto-lock bug? (iPhone X not auto locking)

[j-a-x]

I have auto-lock set to 30 seconds on my iPhone X and I just noticed that if I forget to lock it, it will never actually auto lock. Sometimes the screen dims slightly but then jumps back to normal brightness. I've tried rebooting and changing auto lock preferences but it never actually auto locks.

I'm not sure if this is new to 11.2.1 or if I didn't notice it until now.

Has anybody else noticed this issue? Is there a fix?

 

[mujtaba.mir]

Normal at my end. Kept my phone for auto lock in 30 seconds. Left it flat on the table without looking at it. Screen dimmed first and locked afterwards.

 

[CTHarrryH]

Works fine for me. Locks right on schedule - sorry can't help

 

[JamiLynee]

Mine did that. I changed the setting to auto lock at 1 min and rebooted. Works beautifully every time now

 

[j-a-x]

Mine did that. I changed the setting to auto lock at 1 min and rebooted. Works beautifully every time now

Weird I didn't get any notifications that anybody replied to my post but I just checked and saw your response.

I'll try setting it to 1 min and rebooting and see if it works. Currently my phone has been sitting in a dock charging all morning with the screen on at max brightness. It really bothers me, especially with the potential burn-in issues with OLED displays.
[doublepost=1513786381][/doublepost]I just realized something. It does turn off the screen when it isn't charging, but if it is charging the screen never auto-locks. On Monday when I tested this it wasn't auto locking in either scenario but today it is definitely locking when unplugged...
[doublepost=1513786909][/doublepost]I just set auto lock to 1 minute, rebooted, and now I am not plugged in and have been waiting 2.5 minutes and it has not locked nor has the screen dimmed at all. It now won't auto lock when plugged in or when unplugged.

 

[j-a-x]

I think I figured it out. I turned off "Use attention aware features" and it started locking again.

I think that since I work with my phone next to me, and my phone is propped up so it can probably see my face, the iPhone thought that I was looking at it, even though I was looking at my computer monitor and hoping my phone would sleep until I get a notification to save battery.

With "attention aware" disabled it sleeps as expected both when plugged in and not plugged in.