javascript - cannot pass data from php script to angularjs using angularjs php

one text

when ever i tried to update form response from php script shows undefined.
script.js

$scope.Edit = function() {
  $http.post("update.php", {
    'id' : $scope.id,
       'Name': $scope.Name
    })
    .then(function(response){
        $scope.names = response.data;
        console.log(response.data.success);
     }, function(){
        console.log(response.data.fail);
     })
 }

update.php

<?php
    try {
        header('Access-Control-Allow-Origin: *');
        header('Content-Type: application/json; charset=utf-8');
        $link = new PDO("mysql:host=localhost;dbname=angularjs", "root", "");
        $link->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
        $response = array();
        $json = json_decode(file_get_contents("php://input"), true);
        $Sql = "UPDATE register SET Name = :Name WHERE id = :id";
        $stmt = $link->prepare($Sql);
        $stmt->bindParam(":Name", $json['Name'], PDO::PARAM_STR);
        $stmt->bindParam(":id", $json['id'], PDO::PARAM_STR);
        $stmt->execute();
        $response['success'] = "successfully inserted"; 
    } catch (Exception $e) {
        $response['fail'] = "Error.".$e;
    }
?>

template.html

<div class="container" ng-controller="welcomeController">
    <h1>{{ name }}</h1>
    <p>{{ success }}</p>
    <p>{{ fail }}</p>
    <div class="table-responsive">
        <table class="table table-hover table-borderless">
            <thead>
                <tr>
                    <th>Id</th>
                    <th>Name</th>
                    <th>Email</th>
                    <th>DOB</th>
                    <th>Edit</th>
                    <th>Delete</th>
                </tr>
            </thead>
            <tbody ng-repeat="users in names">
                <tr>
                    <form>
                        <td><input type="text" ng-model="users.id" readonly></td>
                        <td><input type="text" ng-model="users.Name"></td>
                        <td>{{ users.Email }}</td>
                        <td>{{ users.DOB }}</td>
                        <td><button type="submit" ng-click="Edit()" class="btn btn-success">Edit</button></td>
                        <td><button type="submit" ng-click="Delete()" class="btn btn-danger">Delete</button></td>
                    </form>
                </tr>
            </tbody>
        </table>
    </div>
</div>

i need response from php script as updated successfully but it shows undefined. i tried to debug many times i cannot see what mistake i have done.