Log in form doesn't work anymore PHP OOP

i made a login form but can't get trough the last check. It has been days debugging, but i can't find my mistakes. I made a database connection class for data handling with the db, and a user class for userdata handling. The Login function resides inside the user class.

Everything worked untill one point that i can't even recollect.

Database connection class:

        class DbConnect
{
    public $connection;
    public $result;



    public function __construct()
    {
        $this->connectToDb();
    }


    public function __destruct()
    {
        mysqli_close($this->connection);
    }


    private function connectToDb(){

        $this->connection = new mysqli(DB_HOST, DB_USERNAME, DB_PASSWORD, DB_NAME);
        if(mysqli_connect_error()){
            return "can not connect to database ".mysqli_connect_error();
        }
    }


    public function query($query){

        $this->result = $this->connection->query($query);
        return $this->result;
    }


    public function fetch(){

        if(!$this->result){
            return "no results";
        }
        while($row = $this->result->fetch_assoc()){
            $rows[] = $row;
        }
        return $rows;
    }
}

The user class:

class User
{
  private $id = 0;
  private $name = "";
  private $email = "";
  private $password = "";
  private $rights = 0;
  private $consultant = "";


    public function __construct()
    {
    }


        public function setUser($id)
    {

            $db = new DbConnect();
            $query = "SELECT * FROM `real1ze_users` WHERE `user_id` = {$id}";
            $result = $db->query($query);

            if ($result->num_rows > 0) {
                $row = $db->fetch();

                $this->id = $row[0]['user_id'];
                $this->name = $row[0]['user_name'];
                $this->email = $row[0]['user_email'];
                $this->password = $row[0]['user_password'];
                $this->rights = $row[0]['user_rights'];
                $this->consultant = $row[0]['user_consultant'];

            }

    }

    public function getUser()
    {
    $id = $this->id;
    $name = $this->name;
    $email = $this->email;
    $password = $this->password;
    $rights = $this->rights;
    $consultant = $this->consultant;

    return array('id'=>$id,'name'=>$name,'email'=>$email,'password'=>$password,'rights'=>$rights,'consultant'=>$consultant);
    }


    public function loginUser($postEmail, $postPassword)
    {

      $db = new DbConnect();
      $email = mysqli_escape_string($db->connection,$postEmail);
      $password = mysqli_escape_string($db->connection,$postPassword);
      $query = "SELECT * FROM `real1ze_users` WHERE `user_email` = {$email}";
      $result = $db->query($query);

      if ($result->num_rows > 0) {
          $row = $db->fetch();
          $this->setUser($row[0]['user_id']);
          $user = $this->getUser();
          print_r($user);

          //Check if user exists
          if ($row[0]['user_email'] === $email && password_verify($password,$row[0]['user_password']))
          {
              //Set session variables
              $_SESSION['loggedIn'] = true;
              $_SESSION['id'] = $row[0]['user_id'];
              return true;
          }
          else{
              return "User does not exist.";

          }


        }




    }


    public function logoutUser()
    {
        session_destroy();
        header('location: ../login.php');
        return 'User logged out and session destroyed';
    }


    public function checkLoggedIn()
    {
      return $_SESSION['loggedIn'];
    }

}

Login form:

session_start();
//Check if $_POST is set and not empty
if (isset($_POST) && !empty($_POST)){

    //Initiate new user
    $c_user = new User();
    //Log user in with form email and password
    $c_user->loginUser($_POST['user_email'],$_POST['user_password']);


    //If user is logged in
    if ($c_user->checkLoggedIn()){
        //redirect to dashboard
        header('location: index.php');

    }else{
        //Debug
        echo "logged in session not set";
    }

}




/*---------------- PHP Custom Scripts ---------

YOU CAN SET CONFIGURATION VARIABLES HERE BEFORE IT GOES TO NAV, RIBBON, ETC.
E.G. $page_title = "Custom Title" */

$page_title = "Login";

/* ---------------- END PHP Custom Scripts ------------- */

//include header
//you can add your custom css in $page_css array.
//Note: all css files are inside css/ folder
$page_css[] = "your_style.css";
$page_css[] = "lockscreen.min.css";
$no_main_header = true;
include("inc/header.php");
// Include error message script
//include("inc/message.php");

?>
<!-- ==========================CONTENT STARTS HERE ========================== -->
<!-- MAIN PANEL -->
<div id="main" role="main" style="margin-left:0px;">

    <!-- MAIN CONTENT -->

    <form class="lockscreen animated flipInY" method="post">
        <div class="logo">
            <h1 class="semi-bold"><img src="<?php echo ASSETS_URL; ?>/img/real1ze/logo_realize.png" alt="Logo"/></h1>
        </div>
        <div>
            <img src="<?php echo ASSETS_URL; ?>/img/avatars/sunny-big.png" alt="" width="120"/>
            <div>
                <h1>Analytics Log in</h1>

                <div class="input-group" style="margin-bottom: 10px; padding-top: 10px;">
                    <input class="form-control" type="text" placeholder="E-mail" name="user_email" id="email">
                    <div class="input-group-btn">
                        <button class="btn btn-primary" type="submit">
                            <i class="fa fa-user"></i>
                        </button>
                    </div>
                </div>
                <div class="input-group">
                    <input class="form-control" type="password" placeholder="Password" name="user_password" id="password">
                    <div class="input-group-btn">
                        <button class="btn btn-primary" type="submit">
                            <i class="fa fa-key"></i>
                        </button>
                    </div>
                </div>
                <p class="no-margin margin-top-5">
                    Wachtwoord vergeten? <a href="#"> Klik hier</a>
                </p>
            </div>

        </div>
    </form>

</div>