portrait mode doesn't "load"

I have an IPhone 8 Plus. I always used to make portrait.

But now The portrait mode doesn't "load" anymore when I turn it on.

It takes normal photo, like in "normal" mode. No effects, no blurred out background, basically it is not working at all on main camera. And I am trying to find out why.

I don't have this yellow effect ( "When Portrait mode is ready, the lighting effect, like Natural Light, turns yellow."). it's like inactive

I have the latest OS (checked before posting) and I tried Hard Reset. I also have plenty (over 60%) free space on phone.

I use always a person to be visible as a subject. Same way I do before when it was working. 

So I really have no idea why