Google Maps API未顯示道路

我的網站未顯示Google地圖中的道路（我正在使用Google地圖API）。地圖已被設計爲與網站主題相匹配。一段時間以來，道路可見。但它現在已經消失Google Maps API未顯示道路

以下是使用的樣式代碼;

var myCenter=new google.maps.LatLng(40.760845,-73.98611); 
var marker; 

function initialize() 
{ 
var mapProp = { 
    center:myCenter, 
    zoom:16, 
    mapTypeId:google.maps.MapTypeId.ROADMAP 
    }; 

var map=new google.maps.Map(document.getElementById("googleMap"),mapProp); 

var marker=new google.maps.Marker({ 
    position:myCenter, 
    animation:google.maps.Animation.DROP, 
icon: 'http://www.dummywebsite.com/dummyimages/icon.png' 
    }); 

var styles = [ 
    { 
    featureType: "administrative.locatlity", 
    elementType: "geometry.fill", 
    stylers: [ 
     { "color": "#444444" }, 
     { weight: "1.8" } 
    ] 
    },{ 
    featureType: "road", 
    elementType: "geometry.fill", 
elementType: "geometry.stroke", 
    stylers: [ 
     { visibility: "on" }, 
{"color":"#000000"}, 
{ "lightness": 45} 

    ] 
    }, 


{ 
     "featureType": "all", 
     "elementType": "labels.text.stroke", 
     "stylers": [ 
      { 
       "visibility": "off" 
      }, 
      { 
       "color": "#000000" 
      }, 
      { 
       "lightness": 12 
      } 
     ] 
    }, 


    { 
     "featureType": "business", 
     "elementType": "geometry.stroke", 
     "stylers": [ 
      { 
       "color": "#555555" 
      }, 
      { 
       "lightness": 20 
      } 
     ] 
    }, 


{ 
     "featureType": "all", 
     "elementType": "labels.text.fill", 
     "stylers": [ 
      { 
       "visibility": "on" 
      }, 
      { 
       "color": "#888888" 
      }, 
      { 
       "lightness": 25 
      } 
     ] 
    }, 

]; 



map.setOptions({styles: styles}); 



marker.setMap(map); 
} 

google.maps.event.addDomListener(window, 'load', initialize);

尋求寶貴的支持來解決這個問題。

下面是它現在的樣子。道路缺少