So this is which i did create collision, But unreal takes as that :
Did you make sure your render mesh component of your elevator is named exactly “Elevator”? The UCX object needs to have the exact name of the render mesh after UCX_*. I usually follow that with _01 or _02, but I’m not sure if that is a requirement. So for example, if the part of your elevator that moves is called “Elevator”, then name your collision mesh “UCX_Elevator_01”
i am totally sure about it , now im goin to seperate that object and merge. Only this way looks well for this.