How to set up default lighting on new level

I’ve been trying to expand my game project by adding new levels but my first level has some form of default lighting (no light object in the scene what so ever) which does not exist on new levels, nor if I duplicate the existing level.
The result is that any new level constructed ends up being completely black.

I’ve noted that any new levels created have 0 lightmaps (under world setting > lightmass) whilst the old one has 6. But i have found no way of copying these over nor causing the new level to generate new ones.

Could it suffice to, in the level with lighting actors, delete everything else but the necessary things, and open it for creating a new level?

There is no light actors in either of the levels is the thing.
As the screenshots show, if i duplicate the first level the lighting breaks.

You’ll probably need to provide more information. I’m not sure how the original level is lit if there’s no lighting actors.