Slot error doesn't work with ion-checkbox and ion-radio-group Ionic 6 Angular

Hello ,
I am trying slot error , it works for more of the input fields, but seems it doesn’t work for ion-checkbox and for the ion-radio-group .
In the

in the .ts file I have

   private buildForm() {
        this.form = this.formBuilder.group({
            'checkBox':[null, [Validators.required]],
            'radioButtonGroup':[null, [Validators.required]],
        });
    }

and in the .html template

        <ion-item>
            <ion-label position="stacked">Check box</ion-label>
            <ion-checkbox position="fixed" formControlName="checkBox"></ion-checkbox>
            <ion-note slot="error"> Please select</ion-note>
        </ion-item>
        <ion-list >
            <ion-radio-group formControlName="radioButtonGroup" >
                <ion-list-header>
                    <ion-label>Radio button Group</ion-label>
                </ion-list-header>

                <ion-item>
                    <ion-label>Selection1</ion-label>
                    <ion-radio slot="start" value="Selection1"></ion-radio>
                </ion-item>
                <ion-item>
                    <ion-label>Selection3</ion-label>
                    <ion-radio slot="start" value="Selection3"></ion-radio>
                </ion-item>
            </ion-radio-group>
            <ion-note slot="error"> Please select</ion-note>
        </ion-list>

If have some ideas will be great