iPhone 15 Camera App Portrait Mode Depth Of Field is Not Activating

In iPhone 15 iOS 26.5.2, In native camera app portrait mode dept of field is not activating automatically, but switching to studio light option and return back to natural light option then only it activates a dept of field, how to resolve this issue ?

this could be a bug bro. tried restarting iPhone once and checking again?

Yes it done, Restarted iPhone and as well reset setting also done but still i am facing that issue