Angular ControlGroup Validate not resetting values

I am not able to reset my validation once the user enters a value into the UI. In the debugger I can see the value is getting passed into the onModelChange

Should the Validators.required be something that checks the length?

debugger html

<descriptor [model]="model" (modelchange)="onValueChange(model)"></descriptor>

Type Script

@Output() public modelchange: EventEmitter<any> = new EventEmitter();
    public onModelChange(): void {
        this.validate();
        this.modelchange.next(this.getModel());
    }  

    initControlGroup(fb: FormBuilder) : FormGroup {
        return fb.group({
            "value": ['', Validators.required]        
        });
    }

from Angular ControlGroup Validate not resetting values