Webview iframe doesn't work, it doesn't appear on the screen

I need to insert video in my app. I use WebView to insert iframe, but it doesn't work.

const Course = () => {  const route = useRoute();  const course = useSelector((state: RootState) => state.profile.course);  const dispatch = useDispatch();  const {id}: any = route.params;  useEffect(() => {    dispatch(getCourse(id))  }, []);  return (<SafeAreaView><View><TextHeader>{course?.title}</TextHeader><WebView           style={{width: course?.frame_width, height: course?.frame_heigth}}          source={{uri: course?.video}}        /></View></SafeAreaView>  );};

Why does it happen? And how can I fix it?