Exporting models from Maya to SceneKit with animation

I am trying to use my animated model in XCode with SceneKit. I exported my model from Maya with Animation Data in .usd format, then converted it to .usdz with Reality Converter. When I open it in XCode viewer it is animated and everything is fine. However when I try to use it in my app it doesn't animate. On the other hand, when I try with the robot_walk_idle model from Apple's example models, it is animated. Maybe I am missing a option in export settings. Thanks for any help.

import SwiftUI
import SceneKit

struct ModelView: View {
 var body: some View{
    VStack{
        SceneView(scene: SCNScene(named: "robot_walk_idle.usdz"))
    }
 }
}