Auto brightness issue

[kilee]

I'm using XZ and the auto brightness feature is not working properly. 

For example, 

- I cover the illumination sensor with my hand but the brightness is not darken. 

- at that time, I turn off the display and turn it on, the display turn on with the lowest brightness. 

- after that, I leave my hand from the illumination sensor, the brightness is increased. 

- but I cover the sensor again, the brightness is not darken. 

I think this issue happens after the last update(months update for Google security?). 

Does this happen in my device only? 

[kilee]

 I dont have screen protector at all. And I am using sillicon case but this is not affect to the display. 

[Lemmans]

This issue still persist on Oreo and XZ.

On my Xperia Z2 this adjustement works perfect and fast.

On this one is slow and has non sense reactions.

I have no case no cover.