Не работает required в форме

<div class="content"> 
  <form class="form ng-pristine ng-valid ng-valid-last-name ng-valid-maxlength ng-valid-first-name ng-valid-patronymic ng-valid-email ng-valid-mobile-phone ng-valid-mask" name="formSignup" novalidate="" action="step2-1.html" method="POST"> 
    <div class="form__wrapper form1"> 
      <h3 class="form__title"> 
        <span>Контактная информация</span> 
      </h3> 
      <div id="fields-container"> 
        <div class="row form__row"> 
          <div class="col-lg-7 col-md-7 col-sm-7 col-xs-12"> 
            <label class="form__label" for="signupForm.model.lastName">Фамилия</label> 
            <input type="text" class="form__input ng-pristine ng-untouched ng-valid ng-valid-last-name ng-valid-maxlength" name="lastName" required><span></span><span></span> 
          </div> 
        </div> 
        <div class="row form__row"> 
          <div class="col-lg-7 col-md-7 col-sm-7 col-xs-12"> 
            <label class="form__label" for="signupForm.model.firstName">Имя</label> 
            <input type="text" class="form__input ng-pristine ng-untouched ng-valid ng-valid-first-name ng-valid-maxlength" name="firstName" required><span></span><span></span> 
          </div> 
        </div> 
        <div class="row form__row"> 
          <div class="col-lg-7 col-md-7 col-sm-7 col-xs-12"> 
            <label class="form__label" for="signupForm.model.patronymic">Отчество</label> 
            <input type="text" class="form__input ng-pristine ng-untouched ng-valid ng-valid-patronymic ng-valid-maxlength" name="patronymic" required><span></span><span></span> 
          </div> 
        </div> 
        <div class="row form__row"> 
          <div class="col-lg-7 col-md-7 col-sm-7 col-xs-12"> 
            <label class="form__label">Электронная почта</label> 
            <span class="form__row-info">Для получения договора и документов об оплате</span> 
            <div class="form__field"><input type="email" class="form__input js-dadata-email ng-pristine ng-untouched ng-valid ng-valid-email" name="email" required> 
              <span class="form__error">Это поле должно содержать E-Mail в формате example@site.com</span> 
            </div> 
            <span></span><span></span> 
          </div> 
        </div> 
        <div class="row form__row"> 
          <div class="col-lg-7 col-md-7 col-sm-7 col-xs-12"> 
            <label class="form__label">Пароль</label> 
 
            <input type="password" class="form__input js-dadata-password ng-pristine ng-untouched ng-valid ng-valid-password" id="password" name="password" required><span class="form__row-info"></span> 
            <span></span> 
          </div> 
        </div> 
        <div id="signupFormApiError" class="ng-hide"> 
        </div> 
      </div> 
    </div> 
    <div class="form__row form_submit"> 
      <div class="form__submit-wrapper"> 
        <input type="submit" class="form__submit form_submit-next" value="&nbsp;	&nbsp;	&nbsp;	Продолжить&nbsp;	&nbsp;	&nbsp;	" style="padding:11px 48px;"> 
      </div> 
    </div> 
    <!-- ngIf: isConfirm --> 
  </form> 
</div>