Ng-select multiple="true"with checkbox (blur) event fired when I click on checkbox

I was trying to implement (blur) with ng-select multiple with checkboxes,so the everytime I change my model I will not be making api calls .API calls will be made only when ng-select is out of focus. Api will be called on (blur) . But when I click on checkbox which is defined inside ng-select only using ng-template it is triggering the blur event. I want to emit only on blur.

<div  style="width: 100%"  tabindex="0" >

                             <ng-select #mySelect  class="custom" [style]="{'height':'10px', 'width':'100%','border':'2px'}"

                                [items]="lookup.investorKnowledgeSource.asArray"
                                [multiple]="true"
                                [closeOnSelect]="false"
                                [(ngModel)]="it.source"
                                 placeholder="Select Source Of Knowledge Product"
                                [clearable]="false"
                                (ngModelChange)="onChangeKnowledgeSource($event,it)"
                                (blur)="change.emit()"

                               >
                           <ng-template   ng-multi-label-tmp >
                              <span><b>()Selected</b></span>
                          </ng-template>

                            <ng-template ng-option-tmp let-item="item" let-item$="item$" let-index="index">
                                <input id="item-" type="checkbox"  [ngModel]="item$.selected"  [disabled]="item.disabled"/> 
                            </ng-template>
                          </ng-select>

                      </div>