注释不会按照我提供的顺序放在地图视图上

I developed an application, which uses the map view, which has multiple annotations at the same location, but it is not dropping the pins which I provided the order for the annotations. I added annotations from the array, but it is not showing the same order. I need the first object [annotation] to be the top on the location. when user taps on the annotation, it should show the first object as callout. Any suggestions to do the same.I developed an application, which uses the map