Screen random brightens when in locked mode

[AC Question]

Periodically when my S8 is in locked mode (with the date and time showing), it will all of a sudden brighten for no particular reason. I don't have any notifications, messages or anything that would explain why it's happening. Any ideas?

 

[anon(9602380)]

Welcome to Android Central.

If you have auto brightness turned on in your display setting that's what is the cause. Your phone is sensing a change in the lighting in the surroundings around you. Thanks.