Proximity sensor ignored partially?

[inz.mamon]

I have a weird issue with my A2 Lite.
I tried couple of ROMs so far and it's all the same.
When I receive a call and answer it, I bring the phone to my ear and I can see that display goes off - that's good. But, despite keeping the phone close to my ear, the flash light turns on, bt or even airplane mode so it disconnects the call, it changes the screen brightness or mutes the mic during the call. It's like touch sensor was alway on with display off, so I can't even see what I'm touching and switching.
I even went back to stock MIUI to be able to run system check with *#*#64...etc. and proximity sensor works fine.
My problem is similiar to this one: https://forum.xda-developers.com/mi-a2-lite/help/lockscreen-notification-sound-proximity-t3867872.
This drives me crazy!!!
Did anyone have this problem or knows some tricks to fix it (beside smashing the sh..t on the wall)?

 

[keyone72]

I experience the same thing sometimes with stock rom

 

[inz.mamon]

I experience the same thing sometimes with stock rom

That - I didn't expect...
But it has to do something with the Android or kernel maybe. How does it come, that screen is being turned off but not locked (meaning insensitive for touches)?
Weird...
And I'm almost sure, it wasn't like this before... before I installed one of custom ROMs (Arrow maybe). But since then I even went back to stock Pie, so if any firmware/kernel manipulation caused it, with stock - it should've fixed.
I'm starting to dislike daisies...