สอบถามการ Export Data to excel โดย phpspreadsheet หน่อยครับ

<form action="opentesting.php" id="export_filesim" method="post" enctype="multipart/form-data">
	<div class="card-tools">
		<select class="form-control select2bs4" style="border-color: #66adea" id="export_occupier" name="export_occupier" required>
			<option value="0">-- กรุณาเลือก --</option>
			<?php 
				$result = mysqli_query($connect,"SELECT DISTINCT occupier FROM table_sim "); 
				while($row = mysqli_fetch_array($result)){ 
					echo '<option value="'.$row['occupier'].'">'.$row['occupier'].'</option>'; 
				} 
			?>     
		</select>
	</div>
	<div class="card-tools">
		<button type="button" class="btn btn-danger" name="export_file_btn" id="export_file_btn">
			<i class="fa fa-file-excel"></i> Exports File 
		</button>  
	</div>
</form>

date_default_timezone_set("Asia/Bangkok");
	session_start();

	require 'vendor/autoload.php';
    use PhpOffice\PhpSpreadsheet\Spreadsheet;
    use PhpOffice\PhpSpreadsheet\Writer\Xlsx; 
	use PhpOffice\PhpSpreadsheet\Writer\Xls; 

	if(isset($_POST['export_occupier'])){
		$Export_Acc = $_POST['export_occupier'];
		$fileName = 'CHECK_SIM-FILE_'.time();

		$query_sim = "SELECT * FROM table_sim WHERE occupier='".$Export_Acc."' ORDER BY sim_id asc";
		$query_run = mysqli_query($connect,$query_sim);

		if(mysqli_num_rows($query_run)>0){
			$spreadsheet = new Spreadsheet();
			$sheet = $spreadsheet->getActiveSheet();

			$sheet->setCellValue('A1', 'phone');
			$sheet->setCellValue('B1', 'service');
			$sheet->setCellValue('C1', 'simmoney');
			$sheet->setCellValue('D1', 'expiration');
			$sheet->setCellValue('E1', 'occupier');
			$sheet->setCellValue('F1', 'status');
			$sheet->setCellValue('G1', 'note');
			$sheet->setCellValue('H1', 'linegroup');
			$sheet->setCellValue('I1', 'log_user');
			$sheet->setCellValue('J1', 'checksim');

			$rowcount = 2;
			foreach ($query_run as $data){
				$sheet->setCellValue('A'.$rowcount, $data['phone']);
				$sheet->setCellValue('B'.$rowcount, $data['service']);
				$sheet->setCellValue('C'.$rowcount, $data['simmoney']);
				$sheet->setCellValue('D'.$rowcount, $data['expiration']);
				$sheet->setCellValue('E'.$rowcount, $data['occupier']);
				$sheet->setCellValue('F'.$rowcount, $data['status']);
				$sheet->setCellValue('G'.$rowcount, $data['note']);
				$sheet->setCellValue('H'.$rowcount, $data['linegroup']);
				$sheet->setCellValue('I'.$rowcount, $data['log_user']);
				$sheet->setCellValue('J'.$rowcount, $data['checksim']);
				$rowcount++;
			}
			if($NameOccupier == 'Xlsx'){
				$writer = new Xlsx($spreadsheet);
				$final_filename = $fileName.'.xlsx';
			}elseif($Export_Acc == 'Xls'){
				$writer = new Xls($spreadsheet);
				$final_filename = $fileName.'.xls';
			}
			header('Content-Type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet');
			header('Content-Disposition: attachment;filename="'.urlencode($final_filename).'"');
			$writer->save('php://output');
			//$writer->save($final_filename);*/

		}else{
			$_SESSION['status'] = "No Record found to Export";
			header("Location: index.php");
		}
	}