<?php
$user_name = $_POST['user_name'];
$user_password = $_POST['user_password'];
$phone_number = $_POST['phone_number'];
$user_email = $_POST['user_email'];
if (!empty($user_name) || !empty($user_password) || !empty($phone_number) || !empty($user_email)) {
    $host = "localhost";
    $dbUsername = "root";
    $dbPassword = "";
    $dbname = "loginsystem";
    //create connection
    $conn = new mysqli($host, $dbUsername, $dbPassword, $dbname);
    if (mysqli_connect_error()) {
     die('Connect Error('. mysqli_connect_errno().')'. mysqli_connect_error());
    } else {
     $SELECT = "SELECT user_email From users Where user_email = ? Limit 1";
     $INSERT = "INSERT Into users (user_name, user_password, phone_number, user_email,) values(?, ?, ?, ?)";
     //Prepare statement
     $stmt = $conn->prepare($SELECT);
     $stmt->bind_param("s", $user_email);
     $stmt->execute();
     $stmt->bind_result($user_email);
     $stmt->store_result();
     $rnum = $stmt->num_rows;
     if ($rnum==0) {
      $stmt->close();
      $stmt = $conn->prepare($INSERT);
      *$stmt->bind_param("ssis", $user_name, $user_password, $phone_number, $user_email);*
      $stmt->execute();
      echo "New record inserted sucessfully";
     } else {
      echo "Someone already registered using this email";
     }
     $stmt->close();
     $conn->close();
    }
} else {
 echo "All field are required";
 die();
}
?>