Despite your poor attempt at writing the post
I managed to crack the code. Sadly all I can add is that I've experienced something simmilar. It seemed to go away after I fiddled a little, but I'm not sure how I fixed it.
Probably something to do with baking lights or not baking lights lol, but that is as much as I can guess.
I would also really appreciate any expert playmaker sharing some insights into possible reasons for lights becoming dark when loading a scene.
(Also I am not sure if this is isolated to playmaker as I'm pretty sure that back in the day I may have experienced this when learning c#, but I am not sure of that)