Lighting issues (weird lines/circles on 3D objects)

i recently got this weird lighting bug where when i bake my lighting i get these strange lines/circles on everything especially when i lower my lights intensity for a night scene but here is the strangest part as my project is using noise and grain image effect (legacy version before 5.6) and when i turn it on these lines just vanish.
every camera in my scene is using deferred rendering with HDR on.

Scene View Day Scene
Scene View Light “Stains”

Scene View NightScene
Scene View NightScene

strange lines in my day scene while in game (Noise and grain off)
[91692-DayScene.png|91692]

exact same scene but with while in game (Noise and grain on)
[91693-DayScene_NoGrain.png|91693]

Lighting Settings
Light Settings

This is an effect called ‘banding’. It occurs particularly in areas of low light/little contrast in colour, as the gaps are so small that the computer can’t ‘distinguish’ between them. You have, however, stumbled upon the fix for your own problem. In practically every context, the way in which you deal with banding is to simply add noise to your scene, as you have done here. This works because the human eye is surprisingly lenient towards noise, and as the colours have been ‘jittered’ together, your brain fills in the gaps. In actual fact, there is still just as much banding happening, its just that you can’t perceive it.