angular2-Multiselect dropdown selection is not working in ngx-datatable

Question

Screenshot for reference

I have added angular2-multiselect dropdown in ngx-datatable header for filtering the records, I'm binding the same ng-model object for all columns dropdowns, data is binding properly but all dropdowns are disabled. I'm not able to do selection.

<ngx-datatable [NgxTableToolTipChange]="columns" class="material  fixed-header ngx-datatable scroll-vertical" style="width:auto !important" #changeRequesttable
     [ngClass]="{'overlayDiv': blurParamParent,'':!blurParamParent}"
     [rows]="rows"
     [loadingIndicator]="loading$|async"
     [columns]="columns"
     [columnMode]="'toggle'"
     [headerHeight]="isMultiFilter?58:40"
     [footerHeight]="40"
     [rowHeight]="38"
     [reorderable]="true"
     [scrollbarV]="true"
     [scrollbarH]="true"
     [selectionType]="'checkbox'"
     [selected]="selected"
     [displayCheck]="displayCheck"
     (select)='onSelect($event)'
     [messages]="messages">
  <ngx-datatable-column *ngFor="let col of columns" name="{{col.name}}" prop="{{col.prop}}">

      <ng-template let-column="column" ngx-datatable-header-template>
          <span title="{{col.name}}">{{col.name}}</span>
              <span *ngIf="col.prop != 'details' && isAbovethreshold">
                <br *ngIf="isMultiFilter" />
                <angular2-multiselect tabindex="0" *ngIf="isMultiFilter" id="dropdownFilterValues" class="form-control"
                    [data]="bindFilterDropdownData(col.prop)"
                    (onSelect)="onItemSelect($event)" 
                    [(ngModel)]="selectedItems" 
                    [settings]="dropdownSettingsForColumnFilter">
                  </angular2-multiselect>
                    </span>
      </ng-template>
  </ngx-datatable-column>
</ngx-datatable>