Your directional light (Sun) / sky is too strong! It/they just burn out the scene! I’d go lower with their intensity! When you have illumination in the interior, you can fine tune the scene with smaller changes in the lights’ settings and post process.
…do you have enough light bounce set under Lightmass settings?
If you’re using the sun positioning actor then reduce the light intensity of the sun directional light from 75.000 lux to something like 50 lux. Double click the sun actor to get access to it.
You need to have your exposure set to “extended range” in the project settings as well.