[loops] Angular 2 formArrays에서 지정되지 않은 이름 속성이있는 컨트롤을 찾을 수 없습니다.

내 구성 요소에서 formArray를 반복하려고하는데 다음 오류가 발생합니다.

Error: Cannot find control with unspecified name attribute

내 클래스 파일의 논리는 다음과 같습니다.

export class AreasFormComponent implements OnInit {
    public initialState: any;
    public areasForm: FormGroup;

    constructor(private fb: FormBuilder) { }

    private area(): any {
      return this.fb.group({
          name: ['', [Validators.required]],
          latLong: ['', [Validators.required]],
          details: ['', [Validators.required]]
      });
    }

    public ngOnInit(): void {
        this.areasForm = this.fb.group({
            name: ['', [Validators.required]],
            areas: this.fb.array([this.area()])
        });
    }
}

내 템플릿 파일

<form class="areas-form" [formGroup]="areasForm" (ngSubmit)="onSubmit(areasForm.values)">
    <md-input-container class="full-width">
        <input mdInput placeholder="Location Name" type="text" formControlName="name" required>
        <md-error *ngIf="areasForm.get('name').hasError('required')">Please enter the locationName</md-error>
    </md-input-container>
    <md-grid-list cols="1" [formArrayName]="areas">
        <md-grid-tile formGroupName="i"  colspan="1" rowHeight="62px" *ngFor="let area of areasForm.controls.areas.controls; let i = index ">
            <md-grid-list cols="3" rowHeight="60px">
                <md-grid-tile colspan="1">
                    <md-input-container class="full-width">
                        <input mdInput placeholder="Area Name" type="text" formControlName="name" required>
                        <md-error *ngIf="areasForm.get('areas').controls[i].name.hasError('required')">Please enter the area name</md-error>
                    </md-input-container>
                </md-grid-tile>
                <md-grid-tile colspan="1">
                    <md-input-container class="full-width">
                        <input mdInput placeholder="details" type="text" formControlName="details" required>
                        <md-error *ngIf="areasForm.get('areas').controls[i].name.hasError('required')">Please enter the locationName</md-error>
                    </md-input-container>
                </md-grid-tile>
                <md-grid-tile colspan="1">
                    <button md-fab (click)="remove(i)"><md-icon>subtract</md-icon>Remove Area</button>
                </md-grid-tile>
            </md-grid-list>
        </md-grid-tile>
    </md-grid-list>
    <button type="submit" [disabled]="areasForm.invalid" md-raised-button color="primary">Submit</button>
</form>