PHP:将 MySQL 数据导出到 Excel 文件时出现问题

我正在将 MySQL 数据导出到一个 Excel 文件中，该文件包含印地语"数据，但出现了印地语निमà¥à¤¨.

I am exporting MySQL data into an Excel file which contains "Hindi" data but in place of Hindi निमà¥à¤¨ is appearing.

请帮助解决我的问题.我的 PHP 代码是:

Please help in resolving my issue. My PHP code is:

<?php
    include 'connection.php';
    $filename = "currentaffairquestions";  //your_file_name
    $file_ending = "xls";   //file_extention
    mysqli_set_charset($conn,'utf8');
    header("Content-Type: application/vnd-ms-excel");    
    header("Content-Disposition: attachment; filename=$filename.xls");  
    header("Pragma: no-cache"); 
    header("Expires: 0");
    $sep = "\t";
    $sql="SELECT  question_number,question_name,choice1,choice2,choice3,choice4,answer from current_affairs_question_details where id='$_GET[currentaffairid]'"; 
    $result=mysqli_query($conn,$sql);
    while ($property = mysqli_fetch_field($result)) { //fetch table field name
        echo $property->name."\t";
    }

    print("\n");    

    while($row = mysqli_fetch_row($result))  //fetch_table_data
    {
        $schema_insert = "";
        for($j=0; $j< mysqli_num_fields($result);$j++)
        {
            if(!isset($row[$j]))
                $schema_insert .= "NULL".$sep;
            elseif ($row[$j] != "")
                $schema_insert .= "$row[$j]".$sep;
            else
                $schema_insert .= "".$sep;
        }
        $schema_insert = str_replace($sep."$", "", $schema_insert);
        $schema_insert = preg_replace("/\r\n|\n\r|\n|\r/", " ", $schema_insert);
        $schema_insert .= "\t";
        print(trim($schema_insert));
        print "\n";
    }
    ?>