Google Maps drag and dragend event listeners won't work if marker created by click event listener

Question

Just a noob trying to learn, I came out with a problem that when I try to create marker with click event, drag and dragend event listeners won\'t work. Whereas when created

Answer 1

var marker = new google.maps.Marker({
        position: latlng,
        map: map,
        zoom:25,
        title: title,
        draggable:true,
});
var infowindow = new google.maps.InfoWindow({
    content: info 
  });
infowindow.open(map,marker);

google.maps.event.addListener(marker,'drag',function(event) {
    document.getElementById('lat').value = event.latLng.lat();
    document.getElementById('lng').value = event.latLng.lng();
    var infowindow = new google.maps.InfoWindow({
        content: 'Latitude: ' + event.latLng.lat() + '
Longitude: ' + event.latLng.lng()
      });
    infowindow.open(map,marker);
});

google.maps.event.addListener(marker,'dragend',function(event) 
        {
    document.getElementById('lat').value =event.latLng.lat();
    document.getElementById('lng').value =event.latLng.lng();
    var infowindow = new google.maps.InfoWindow({
        content: 'Latitude: ' + event.latLng.lat() + '
Longitude:'+`event.latLng.lng()
      });
    infowindow.open(map,marker);
});