使用PHP API将数据插入DB时出错,但没有出现在错误日志中

因此,目前我无法在Apache错误日志和MySQL错误日志中找到正在生成的任何新错误。由于我没有正确设置我的mysqli_query(),我不完全确定哪里出了问题,因为正在生成最后一个错误。因此,我对其进行了编辑,现在我没有产生任何错误,但是我的数据库表中没有任何内容。

目前,我的设置是这样的:

-rest/
 -inc/
   -config.php
   -conn.php
   -user.php
 -user_handle.php
user_handle.php
 <?php 



    error_reporting(-1);

    include_once("inc/config.php");
    include_once("inc/user.php");
    include_once("inc/conn.php");

    $user = new User();

    header("Content-Type:application/json; charset=UTF-8;");

    $json_str = file_get_contents('php://input');
    $obj = json_decode($json_str);

    if($obj->type === "reg") {
        $email = $obj->email;
        $password = $obj->password;
        $ip = $obj->ip;

        $sub_user = $user->register($email, $password, $ip);
        return $sub_user;
    }  else {
        return "Error";
    }

?>
user.php
<?php 



    include "conn.php";



    class User {


        public $password;
        public $email;
        public $ip;


        // User Registration
        function register($email, $password, $ip) {
            $dbC = new MySQL();

            $dbC->connect();

            $query = "INSERT INTO users (email, password, ip) VALUES ('".$email.", '".$password."', '".$ip."')";

            $result = mysqli_query($dbC->connect(), $query);

            if ($result === TRUE) {
                return "Success";
            } else {
                return "Error";
            }
        }

    }


?>
conn.php
<?php 



    include_once('config.php');

    class MySQL extends Dbset{

        var $myconn;

        function connect() {
            $dbConfig = new Dbset();

            $con = mysqli_connect("".$dbConfig->serverName."", "".$dbConfig->userName."", "".$dbConfig->passCode."", "".$dbConfig->dbName."");
            if (!$con) {
                die('Could not connect to database!');
            } else {
                $this->myconn = $con;
                echo 'Connection established!';}
            return $this->myconn;
        }
        function close() {
            mysqli_close($myconn);
            echo 'Connection closed!';
        }

    }
?>
config.php
    <?php 



    // MySQL Connection 

    class Dbset {

        protected $serverName;
        protected $userName;
        protected $passCode;
        protected $dbName;

        function dbset() {
            $this->serverName = 'localhost';
            $this->userName = 'mimbl';
            $this->passCode = 'password';
            $this->dbName = 'mimbl';
        }
    }

    // End of MySQL Connection 


?>

任何人都知道哪里可能产生错误?