ผมดึงข้อมูลหมุด google map จาก mysql แล้วบังคับ map ไม่ได้ครับ

<script>
  function initMap() {
		var mapOptions = {
			center: {lat: 13.847860, lng: 100.604274},
			zoom: 5,
		}
		var maps = new google.maps.Map(document.getElementById("map"),mapOptions);
		var marker, info;
		$.getJSON( "json.php", function( jsonObj ) {
			//*** loop
			$.each(jsonObj, function(i, item){
				marker = new google.maps.Marker({
					position: new google.maps.LatLng(item.dorm_lat, item.dorm_lon),
					map: maps,
					title: item.dorm_name
				});
				info = new google.maps.InfoWindow();
				google.maps.event.addListener(marker, 'click', (function(marker, i) {
					return function() {
					info.setContent(item.dorm_name);
					info.open(maps, marker);
				}
				})(marker, i));
			}); // loop
		});
	}
</script>