Some pages are missing in the sitemap

[saeedesmaili]

I'm using this plugin in my gatsby blog. Everything looks and works fine, except a page that isn't in the sitemap.xml file. It seems that sitemap ignores some pages. How can I troubleshoot this problem or fix it?

blog's home page: https://datanerd.blog
sitemap: https://datanerd.blog/sitemap-pages.xml
the page that I can't see in the sitemap: https://datanerd.blog/data-analysis-with-python-movielens/

gatsby version: 3.4.0
gatsby-plugin-advanced-sitemap: 1.6.0
I haven't added any options (for example to exclude any page) in the gatsby-config file.