Ember select prompt value is displayed though selection property is not null

Template:

{{view "select" viewName="someFilter"
                content=filterContent
                optionLabelPath="content.name"
                        prompt="Please selct on option"
                selection=selectedOption}}

Controller :

export default Ember.ArrayController.extend({
  selectedOption: null,
  filterContent: [{name:"option1",content:["1","2"]},{name:"option2",content:["2","3"]},{name:"option3",content:["1","3"]}],

});

On intial load when selectedOption is null prompt is getting displayed which is fine. Now if i select some option and then navogated away to another route. When i came back selctedOption value is eet as last selected option but dealut value is still shown as "Please selct on option" (Prompt value) and not the option which was selected before navigating away.

Please let me know any thoughts on this issue.