Expo(react-native)によるマップが表示されない現象 for Android

React-native によるmapの実装 (Expo) for Android.

React-native(Expo)でmap機能を実装しようとしたところMapの空間（空白）だけ表示されMap自体が表示されない。
解決方法お願いします！！

<HomeScreen.js>

import React from 'react';
//import T from 'prop-types';
import MapView from 'react-native-maps';
import { StyleSheet, Text, View } from 'react-native';
import { Touchable } from '../../components';
import s from './styles';

const noop = () => {};

const HomeScreenView = () => (
  <View style={s.container}>
    <Touchable>
      <Text>button</Text>
    </Touchable>
    <Text>Hello, World!</Text>
    <MapView
    style={{flex:1}}
    Region={{
      latitude: 37.78825,
      longitude: -122.4324,
      latitudeDelta: 0.0922,
      longitudeDelta: 0.0421,
    }}
  />
  </View>
);

/*
HomeScreenView.propTypes = (

)
*/

export default HomeScreenView;

<App.js>

import HomeScreen from './src/screens/HomeScreen';

export default HomeScreen

<app.json>

{
  "expo": {
    "name": "sample",
    "slug": "sample",
    "privacy": "public",
    "sdkVersion": "34.0.0",
    "platforms": [
      "ios",
      "android",
      "web"
    ],
    "version": "1.0.0",
    "orientation": "portrait",
    "icon": "./assets/icon.png",
    "splash": {
      "image": "./assets/splash.png",
      "resizeMode": "contain",
      "backgroundColor": "#ffffff"
    },
    "updates": {
      "fallbackToCacheTimeout": 0
    },
    "assetBundlePatterns": [
      "**/*"
    ],
    "ios": {
      "supportsTablet": true
    },
    "android":{
      "config":{
        "googleMaps":{"apiKey":"API-KEY"}
      }
    }
  }
}