Cómo validar OwnerId duplicado en formArray . Estoy intentando instalar este @rxweb/reactive-form-validators pero no funciona. Este es mi código de demostración Stackblitz

HTML:

 <div class="col-12 col-sm-12 col-md-12 col-lg-12 col-xl-12 d-flex" [formGroupName]="i" *ngFor="let driver of nameDriverControl.controls; let i=index"> <label>{{i+1}}.Name</label> <input class="form-control" type="text" id="name" name="name{{i}}" formControlName="name" ><br/> <label>{{i+1}}.Owner Id</label> <input class="form-control" type="text" id="ownerId" name="ownerId{{i}}" inputmode="numeric" dashFormat formControlName="ownerId" maxLength="14"> <div class="col-2 col-sm-2 col-md-2 col-lg-2 col-xl-2"> <div class="form-group mb-0" *ngIf="i !== 0"> <button class="btn btn-danger" (click)="removeDriver(i)"> Delete </button> </div> <div class="form-group mb-2"> <button *ngIf="i >= 0 && i < 1" type="button" [hidden]="nameDriver.length > 3" (click)="addDriver()" class="btn btn-primary"> Add </button> </div> </div> </div>

Componente

 createDriver () { return new FormGroup({ name: new FormControl(null, Validators.required), ownerId: new FormControl(null, Validators.required) }) }