Help my phone display settings keep going onto auto mode

[Big Dan]

Until yesterday everything was fine. Something changed though not sure how/why.

I have my brightness set to a certain level. But my phone brightness display keeps going on Auto mode and keeps going darker. It also keeps turning off Wifi, I'm assuming as a result of the same glitch. I keep fixing this, it keeps reverting. This is within a minute or two.

What on earth is going on?

FYI I have a Samsung S5 running Lollipop.

 

[chanchan05]

Are you using power saver? That seems like normal power saver behavior.