scene switching issue?

my project has a few scenes and runs as desired before
but after adding a loading scene before the main scene, the main scene looks like this after switching into the main scene


the skybox added as a background scene is not showing and the ship at the side also does not display its texture properly (these aren’t the only problems)

if the project is start in this scene instead of the loading scene, all is well, only if the project is started from the loading scene

does anyone know why this is happening and could help me out on this?