Ошибка при создании формы регистрации

var capkeygoogle; 
 
function CheckForm() { 
  var pass1 = document.forms[0].password.value; 
  var pass2 = document.forms[0].password2.value; 
  var login = document.forms[0].login.value; 
  var email = document.forms[0].email.value; 
  var checkbox1 = document.getElementById('checkbox'); 
  if (!(document.getElementById('login').checkValidity())) { 
    $('.alert').css('background', 'red'); 
    Alert_Opoveshenie('Login is incorrect!'); 
    return false 
  } 
  if (!(document.getElementById('email').checkValidity())) { 
    $('.alert').css('background', 'red'); 
    Alert_Opoveshenie('E-mail is incorrect!'); 
    return false 
  } 
  if (!(document.getElementById('password').checkValidity())) { 
    $('.alert').css('background', 'red'); 
    Alert_Opoveshenie('Password №1 is incorrect!'); 
    return false 
  } 
  if (!(document.getElementById('password2').checkValidity())) { 
    $('.alert').css('background', 'red'); 
    Alert_Opoveshenie('Password №2 is incorrect!'); 
    return false 
  } 
  if (pass1 != pass2) { 
    $('.alert').css('background', 'red'); 
    Alert_Opoveshenie('Password mismatch!'); 
    return false 
  } 
 
 
  $.ajax({ 
    url: 'Registration.php', 
    type: 'POST', 
    data: { 
      login: login, 
      password: pass1, 
      email: email, 
      capkeygoogle: capkeygoogle 
    }, 
    success: function(res) { 
      if (res.color == 'green') { 
        document.location.href = ""; 
        return true 
      } else { 
        $('.alert').css('background', res.color); 
        Alert_Opoveshenie(res.message); 
        return false 
      } 
    }, 
    error: function() { 
      $('.alert').css('background', 'red'); 
      Alert_Opoveshenie('Error!'); 
      return false 
    } 
  }); 
} 
 
function mySuperFunction(captchaKey) { 
  capkeygoogle = captchaKey; 
} 
 
function Alert_Opoveshenie(Text) { 
  document.getElementById("alert").innerHTML = Text; 
  $('.alert').animate({ 
    bottom: '10px', 
    opacity: '1' 
  }, 1000, function() { 
    // После показа убираем его 
    var alertHide = setInterval(function() { 
      $('.alert').animate({ 
        bottom: '-100%', 
        opacity: '0' 
      }, 1000); 
      clearInterval(alertHide); 
    }, 2000); // Время "жизни" алерта 2 секунды. 
  }); 
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> 
<form> 
  <input type="text" class="login__input" name="login" id="login" placeholder="Username" required pattern="^[a-zA-Z0-9-_\.]{5,20}$" title="LOGIN can consist of 5 (five) to 20 (twenty) characters from: English characters (lower case), numbers and signs - (dot), (dash), (bottom_incident)" 
    autocomplete="off"> 
  <input type="email" class="login__input" name="email" id="email" placeholder="Email" required> 
  <input type="password" class="login__input" name="password" id="password" placeholder="Password" required pattern="(?=(.*[0-9]))(?=.*[a-zа-я])(?=(.*[A-ZА-Я]))(?=(.*)).{6,20}" title="The password can consist of 6 (six) to 20 (twenty) characters, you must have at least one digit, one capital letter, one small letter"> 
  <input type="password" class="login__input" name="password2" id="password2" placeholder="Repeat Password" required pattern="(?=(.*[0-9]))(?=.*[a-zа-я])(?=(.*[A-ZА-Я]))(?=(.*)).{6,20}" title="The password can consist of 6 (six) to 20 (twenty) characters, you must have at least one digit, one capital letter, one small letter"> 
  <input type="button" name="reg" id="registration" value="Register" onclick="CheckForm();"> 
</form> 
<div class="alert" id="alert">Оповещение</div>