simpel

if(isset($_POST['reg_submit'])){

        if(!empty($_POST['reg_username']) && !empty($_POST['reg_password']) && !empty($_POST['reg_email'])){

            $username = filterRegister($_POST['reg_username']);
            $password = $con->real_escape_string(md5($_POST['reg_password']));
            $email = $con->real_escape_string($_POST['reg_email']);
            $gender = $con->real_escape_string($_POST['reg_gender']);
            $look = $register['look'];
            $credits = $register['credits'];
            $duckets = $register['duckets'];
            $points = $register['points'];
            $motto = $register['motto'];

            $data = $con->query("SELECT * FROM users WHERE username = '$username' ");

            if(!mysqli_num_rows($data) > 0){

                $data = $con->query("SELECT * FROM users WHERE mail = '$email' ");

                if(!mysqli_num_rows($data) > 0){