CustomAnnotationView Changes to MKAnnotation in MapKit - objective-c

Question

Hello Everyone i am new in developing app for I-Phone I have stuck in the Custom ANNotationView in mapKit. When i load map first Time it shows correctly Custom View , But after scrolling map it become the red colored PIN (default annotation in MapKit). Kindly Help me . Thank You in advance.
I am using the following code in viewForAnnotation delegate
- (MKAnnotationView *)mapView:(MKMapView *)mapView viewForAnnotation: (id<MKAnnotation>)annotation
{
UIImageView *AvatarView=[[UIImageView alloc]initWithFrame:CGRectMake(0,0, 30, 30)];
AvatarView.layer.cornerRadius =AvatarView.frame.size.width / 2;
AvatarView.layer.masksToBounds = YES;
AvatarView.layer.borderColor =(__bridge CGColorRef)([UIColor colorWithRed:34.0/255.0 green:28.0/255.0 blue:36.0/255.0 alpha:1.0]) ;
AvatarView.layer.borderWidth = 1.0;
AvatarView.layer.zPosition=1;
MKPinAnnotationView* pinView =
(MKPinAnnotationView *)[mapView dequeueReusableAnnotationViewWithIdentifier:#"CustomPinAnnotationView"];
if (!pinView)
{
// Try to dequeue an existing pin view first.
MKAnnotationView *annotationView = [[MKAnnotationView alloc] initWithAnnotation:annotation
reuseIdentifier:#"CustomPinAnnotationView"];
// If an existing pin view was not available, create one.
//pinView.animatesDrop = YES;
annotationView.canShowCallout = YES;
if([[responseDataArray objectAtIndex:k] valueForKey:#"thumbPath"]!=nil && [[[responseDataArray objectAtIndex:k] valueForKey:#"thumbPath"] length]>0)
{
NSString *imgPath =[NSString stringWithFormat:#"%#%#",WebSiteUrl,[[responseDataArray objectAtIndex:k] valueForKey:#"thumbPath"]];
k++;
NSString* webStringURL = [imgPath stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL* url = [NSURL URLWithString:webStringURL];
NSString *imageName = [placeholderImageArray objectAtIndex:(arc4random() %placeholderImageArray.count)];
[AvatarView sd_setImageWithURL:url placeholderImage:[UIImage imageNamed:imageName]];
}
[annotationView addSubview:AvatarView];
return annotationView;
}
else
{
k=0;
pinView.annotation = annotation;
}
return pinView;
}
I am using the following code to add Annotation
MKPointAnnotation *myAnnotation = [[MKPointAnnotation alloc] init];
myAnnotation.coordinate = coord;
myAnnotation.title = titleStr;
myAnnotation.subtitle = #"Best bar in Town";
[myLocation addAnnotation:myAnnotation];
It never goes to else part. I don't know what is the problem. Please help me to solve out this problem. A big thanks to You.