GMAP creating double marker on same position and not updating marker when values updated?

I am setting number of markers(using png icons) on gmap at the same time but when I update the list the markers should be updated accordingly.

But they didn't gets updated immediately with the list.

First I am clearing the map from markers with this code

 for (var i=0; i<this.markerList.length; i++) {     
    this.markerList[i].setMap(null);
}    
// Reset the markers array
this.markerList = [];  

Than I am setting the markers again with my initial code which run at the time of mounted

 this.markers = this.mappedListings;
    this.markerList = this.markers.map((home) => {
      var price = home.info.listingPrice
      var favList =  this.getFavIconOnMap(home);          
      var url = this.setMarkerIcon(home,favList);              
     var homeInfo = home.info;
      let marker = new this.google.maps.Marker({            
        position: {
          lat: parseFloat(home.position.lat),
          lng: parseFloat(home.position.lng),
        },
        scaledSize: new this.google.maps.Size(18, 18),
        icon: url,
         label: { color: '#FFFFFF', fontWeight: 'bold', fontSize: '10px', text:String(price)} 
      });

I am changing the image url by these conditions

 var url=''
   if(home.info.status === "CT" && favList == false){
         url = new google.maps.MarkerImage(
          '/assets/icons/contigment.png',
            new google.maps.Size(108, 120), //adjust size of image placeholder  
            new google.maps.Point(-25, -27), //origin
            new google.maps.Point(-69,0) //anchor point
          );
       } 
      else if(home.info.status === "CT" && favList == true){
         url = new google.maps.MarkerImage(
          '/assets/icons/contigmentheart.png',
             new google.maps.Size(108, 120), //adjust size of image placeholder  
            new google.maps.Point(-25, -27), //origin
            new google.maps.Point(-69,0) //anchor point
          );
       } 

The First Problem is

When I update values in my marker gets updated but there is no change on map until I zoom in or zoom out the map. I Tried every function at the time of updating which I using in my app.

The Second Problem is

When marker updates after zoom in or zoom out of map , then after two three times of update it shows previous marker behind the current marker on map, don't know how it is showing double marker for the same although I empty map every time.

Here is the first picture of marker before updating.

Here is the Second Picture after updated values.

Again when I change List to previous values, according to logic there should be first image but behind this it is showing a part of second image also, as you can see in image below

Not so familiar with gmaps, hope I elaborate the problem clearly.