gozap_api/Reports/Asset/index.php

<?php

// Include Database connection
include_once "../../include/DB.php";
// Include SimpleXLSXGen library
include_once "../../include/SimpleXLSXGen.php";
$id = 0;
$fromDate="";
$toDate="";
$assetSqlfilter="";
$assets = [
  ['#', 'Asset ID', 'Asset Name', 'IsInServiceCenter', 'Asset Category', 'Asset Created At', 'Asset Updated At']
];

if (isset($_GET["fromDate"]) && !empty($_GET["fromDate"]) && isset($_GET["toDate"]) && !empty($_GET["toDate"])) {
  $fromDate=$_GET["fromDate"];
  $toDate=$_GET["toDate"];
  $assetSqlfilter="AND (asset.CreatedDate BETWEEN '$fromDate' AND '$toDate')";
}
if (isset($_GET["AssetID"]) && !empty($_GET["AssetID"])) {
  $AssetID=$_GET["AssetID"];
  $assetSqlfilter .="AND asset.AssetID='$AssetID'";
}
include 'asset_report.php';

$xlsx = SimpleXLSXGen::fromArray($assets,'Assets');
$xlsx->downloadAs('asset_report.xlsx'); // This will download the file to your local system

// $xlsx->saveAs('asset_report.xlsx'); // This will save the file to your server

echo "<pre>";
print_r($assets);