Problem with imported level from Maya

I’m stuck with a problem, I have no problem with this in Unity but this problem occurs in Unreal for me.

I’ve imported a level I’ve made in Maya (floor and walls only). But my character just falls through the floor - but when I put the player above the level he falls flat in the same height as the walls - so somehow Unreal put colliders around the whole level.

By default it will try to generate collision meshes for whatever you import, Chances are the collision meshes aren’t good so you need to open up the static mesh and edit the collision