AngularJS is not showing data in Hindi language

I am trying to fetch MYSQL database data in AngularJS, Data is in hindi language. Database collation set to ‘utf8_unicode_ci’.

<div ng-controller="postController" ng-init="display_data()">
    <table class="table table-bordered">
            <th>Post id </th>
            <th>Post Title</th>
            <th>Post Details</th>
            <th>Post Status</th>
        <tr ng-repeat="x in posts" >
    var app = angular.module("concept", []);
    app.controller("postController", function ($scope, $http) {
        $scope.display_data = function () {
                method: 'GET',
                url: 'getPost.php'
            }).then(function (post) {
                $scope.posts =;
            }, function (error) {
                alert("Something went wrong!!");

No error in console

Here is php code:

header('Content-Type: text/html; charset=utf-8');
$conn = mysqli_connect("localhost","root","","concept") or die(mysqli_error()) ; 
$output = array();

$query = "SELECT * FROM userpost";

    while($row = mysqli_fetch_array($result))
        $output[] = $row;
    echo json_encode($output);


code running on local server.

Source: AngularJS