I believe you, it’s simply that not everything that creates light is an actual light! If there are no sources of light, then Lit and Unlit will look the exact same on a sprite.
Again, if you can show your world outliner list (I am assuming it isn’t a long list judging by the picture) we can at least look at it and see if there is anything.
Additionally- try deleting the post processing. If that doesn’t fix it you can use CTRL+Z to undo, I know they can be hard to set up with so many moving parts.
Other than that, we need more information to help you any further, which is why I am requesting a picture. 