error generating xml sitemap
<?xml version="1.0" encoding="UTF-8"?>

<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
 <sitemap>
  <loc>https://www.eastamps.com/sitemap/1.html</loc>
 </sitemap>
 <sitemap>
  <loc>https://www.eastamps.com/sitemap/2.html</loc>
 </sitemap>
</sitemapindex>