Как реализовать проверку ввода реактивной формы Angular

Вот моя форма ниже: Текущие проверки ошибок в форме не работают.

<div formGroupName = "deliveryAddress">
<div class = "row mb-4">
    <div class = "col mb-4">
        <label class = "form-label">First Name</label>
        <input id = "firstName" class = "form-control fw-bold" type = "text" formControlName = "firstName"
            (change) = "saveToDataStore()">

        <div *ngIf = "firstName.invalid && (firstName.dirty || firstName.touched)" class = "alert alert-danger">
            <div *ngIf = "firstName.hasError('required')">
                First Name is required.
            </div>
        </div>
    </div>

    <div class = "col mb-4">
        <label class = "form-label">Last Name</label>
        <input id = "lastName" class = "form-control fw-bold" type = "text" formControlName = "lastName"
            (change) = "saveToDataStore()">

            <div *ngIf = "lastName.invalid && (lastName.dirty || lastName.touched)" class = "alert alert-danger">
                <div *ngIf = "lastName.hasError('required')">
                    Last Name is required.
                </div>
            </div>
    </div>

    <div class = "row mb-4">
        <div class = "col">
            <label class = "form-label">Phone Number</label>
            <input id = "phone" class = "form-control fw-bold" type = "phone" formControlName = "phone"
                (change) = "saveToDataStore()">
        </div>
    </div>
</div>

Вот объявление формы в компоненте:

private initCheckoutForm = () => {
this.checkoutForm = this.formBuilder.group({
  deliveryAddress: this.formBuilder.group({ 
    firstName: ['', Validators.required],
    lastName: ['', Validators.required],
    phone: ['', Validators.required],
    address1: ['', Validators.required],
    address2: [''],
    useAsBillingAddress: [''],
  }),
  applianceDelivery: this.formBuilder.group({ 
      deliveryDate: ['', Validators.required],
      specialInstructions: [''],
  }),
  paymentMethod: this.formBuilder.group({ 
      paymentType: ['', Validators.required],
      cardNumber: ['', Validators.required],
      expMonth: ['', Validators.required],
      expYear: ['', Validators.required],
      CVV: ['', Validators.required],
      defaultCreditCard: [''],
  })
});
    console.info('this.checkoutForm', this.checkoutForm.value);
  }