FILTER_VALIDATE_EMAIL отклонил действительный адрес электронной почты

Question

В настоящее время я тестирую свое приложение в проекте, над которым я работаю. Я удивлен, увидев, что FILTER_VALIDATE_EMAIL сообщает мне, что мой адрес электронной почты 'kwasikm@yahoo.co.uk' недействителен. Где-то должно быть что-то спрятано. Я надеюсь, что кто-то может мне помочь. Как показано ниже

<?php
if(isset($_POST['register-submit'])){
    require 'dbh.inc.php';
    $fullname       =  $_POST['fullname'];
    $emailaddress   = $_POST['emailaddress'];
    $username       =  $_POST['username'];
    $password       = $_POST['password'];
    $passwordAgain  =  $_POST['passwordAgain'];
    $usersEmailcode = password_hash($username,PASSWORD_DEFAULT + microtime());

     if(empty($fullname)){
         header("Location: ../register.php?error=emptyname");
         exit();
     }else if(!preg_match("/^[a-zA-Z ]*$/",$fullname)){
         header("Location: ../register.php?error=onlyLetters");
         exit();
     }
     if(empty($emailaddress)){
         header("Location: ../register.php?error=emailEmpty");
         exit();
         //email validation . problem here
     }else if(!filter_var($emailaddress,FILTER_VALIDATE_EMAIL));
     header("Location: ../register.php?error=invalidEmail");
     exit();

     if(empty($username)){
         header("Location: ../register.php?error=usernameEmpty");
         exit();
     }else if(strlen($username)<5){
         header("Location: ../register.php?error=usernameShort");
         exit();
     }else if(!preg_match("/^[a-zA-Z0-9]*$/",$username)){
         header("Location: ../register.php?error=onlyNumAndLetters");
         exit();
     }

     if(empty($password)){
         header("Location: ../register.php?error=pwdEmpty");
         exit();
     }else if(strlen($password)<6){
         header("Location: ../register.php?error=pwdShort");
         exit();
     }else if(!preg_match("#[0-9]+#",$password)){
         header("Location: ../register.php?error=oneNumberAtLeast");
         exit();
     }else if(!preg_match("#[A-Z]+#",$password)){
         header("Location: ../register.php?error=upperCase");
         exit();
     }else if(!preg_match("#[\W]+#",$password)){
         header("Location: ../register.php?error=specialChar");
         exit();
     }
     if(empty($passwordAgain)){
         header("Location: ../register.php?error=pwdAgainEmpty");
         exit();
     }else if($passwordAgain !== $password){
         header("Location: ../register.php?error=noMatch");
         exit();
     }
     $sql = "SELECT usersEmail,usersUsername FROM users WHERE usersEmail=? AND usersUsername=?";
     $stmt = mysqli_stmt_init($conn);
     if(!mysqli_stmt_prepare($stmt,$sql)){
         header("Location: ../register.php?error=sqlError");
         exit();
     }else{
         mysqli_stmt_bind_param($stmt,"ss",$emailaddress,$username);
         mysqli_stmt_execute($stmt);
         $result = mysqli_stmt_store_result($stmt);
         $resultCheck = mysqli_stmt_num_rows($result);
         if($resultCheck > 0){
             header("Location: ../regsiter.php?error=userTaken");
             exit();
         }else{
             $sql = "INSERT INTO 
                     users(usersName,userEmail,usersUsername,usersPassword,usersEmailcode)
                     VALUES(?,?,?,?,?)";
            $stmt = mysqli_stmt_init($conn);
             if(!mysqli_stmt_prepare($stmt)){
                 header("Location: ../regsiter.php?error=sqlError");
                 exit();
             }else{
                 $pwdHashed = PASSWORD_HASH($password,PASSWORD_DEFAULT);
                 mysqli_stmt_bind_param($stmt,"sssss",$fullname,$emailaddress,$username,$pwdHashed,$usersEmailCode);
                 mysqli_stmt_execute($stmt);

                 //send account activation email
                  $to = $email;
                  $url = "http://marksmandigital.net/activate.php?email=".$emailaddress ."&usersEmailcode=".$usersEmailcode;
                  $from = "info@marksmandigital.net";
                  $subject = 'Activate your Account!';
                  $message ='<p>Click the link below to verify your account!</p>';
                  $message .= '<p><a href="'.$url.'">"'.$url.'"</a></p>';
                  $headers = "From: Marksman <info@marksmandigital.net>\r\n";
                  $headers .= "Reply-To:info@marksmandigital.net\r\n";
                  $headers .= "Content-type:text/html\r\n";
                  mail($to,$subject,$message,$headers);

                 header("Location: ../register.php?register=success");
                 exit();
             }
         }
     }
     mysqli_stmt_close($stmt);
     mysqli_close($conn);
}else{
    header('Location: ../register.php');
    exit();
}

Есть ли способ обойти это /. html форма здесь

<form method="post" action="includes/register.inc.php" class="form">
         <div class="form-row">
         <div class="form-group col-md-12">
          <input type="text" name="fullname" class="form-control" placeholder="Enter Your Full Name">
         </div>
         </div>
         <div class="form-row">
         <div class="form-group col-md-12">
          <input type="text" name="emailaddress" class="form-control" placeholder="Your Email Address">
         </div>
         </div>
         <div class="form-row">
         <div class="form-group col-md-12">
          <input type="text" name="username" class="form-control" placeholder="Choose A Username">
         </div>
         </div>
         <div class="form-row">
         <div class="form-group col-md-12">
          <input type="password" name="password" class="form-control" placeholder="Choose A Password">
         </div>
         </div>
          <div class="form-row">
         <div class="form-group col-md-12">
          <input type="password" name="passwordAgain" class="form-control" placeholder="Repeat  Your Password">
         </div>
         </div>
         <div class="form-row">
           <div class="form-group col-md-12">
            <input type="submit" name="register-submit" class="form-control btn btn-success"         value="SUBMIT REGISTRATION">
           </div>
         </div>
         </form>