Could I change the root of my sitemap.xml path?

Question

This is my resulting xml file.

<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9">
  <url>
    <loc>http://localhost:5000/</loc>
   </url>
</urlset>

I would like to change http://localhost:5000 to https://www.mywebpage.es and I don't know where I've got to change it. I tried to siteMapNode.Url = "...." + GetPath(); and it doesn't work or change my Mvc.sitemap. I need to have always the same root, developer environment or production environment...