This is the code for register form, I’ve inspected and inspected and still can’t see any problem….
<form id="join-form" action="https://localhost/***/wp-login.php?action=register" class="text" method="post">
<input id="user_login" name="" type="text" value="" />
<input id="user_email" name="user_email" type="email" value="" />
<input id="pass1" name="pass1" type="password" value="" />
<div class="submit-button-ctn">
<input type="submit" class="submit-button" id="join-submit" value="join" />
</div>
</form>