angular.js:13920 TypeError: Cannot create property '$isNew' on string '1'

[sagarjethi]

angular.js:13920 TypeError: Cannot create property '$isNew' on string '1' at suggest.box.js:584 at angular.js:17385 at m.$digest (angular.js:17524) at m.$apply (angular.js:17790) at l (angular.js:11831) at J (angular.js:12033) at XMLHttpRequest.t.onload (angular.js:11966)

<my-component list-items="listInterst" smodel="interest" id="interst"></my-component>

app.directive('myComponent', [function() {
    return {
        restrict: 'E',
        scope: {
            listItems:'=listItems',
            selectedItems: '=',
            onChange: '&',
            smodel:'=smodel'
        },
        templateUrl:'/app/templete/interst.html',
        link: function(scope){
            console.log(scope.listItems);
            console.log(scope.smodel);
        }


    }
}]);

<div az-suggest-box sb-list="listItems" sb-model="smodel" class="suggest-box">
    <div class="select">
        <div class="input">
            <div sb-selection-item class="selection-item">
                {{s.label}}&nbsp;<span sb-remove-item-from-selection class="rem-btn"><i class="fa fa-times"></i></span>
                </div>
            <input sb-trigger-area sb-type-ahead tabindex="1">
            </div>
        <button sb-trigger-area><i class="fa fa-chevron-down"></i></button>
        </div>
    <ul class="dropdown">
        <li sb-dropdown-item class="item">{{i.label}}</li>
        </ul>
    </div>