It is recommended to keep a sitemap.xml up-to-date and free of errors*.
If you merge the content of
www.example.com/one.html you probably (ideally) redirect them both to
Other URLs that have been removed may serve an HTTP status 404 (not foud) or similar.
In order to make crawling your website easy Google recommends to use only URLs in your sitemap that serve HTTP Status 200.
If you have URLs in your sitemap causing errors you can see warnings in your Google Search Console property:
Long story short:
- Make sure to 301 redirect your old URLs to your new URL.
- Update your Sitemap and delete all URLs that do not serve HTTP 200 directly
*For further possible errors regarding sitemaps see: