Google XML Sitemaps not all pages display

Hi ,

I am using plugin Google XML Sitemaps to generate site map in my site.

I have generated site map , It will gives me monthly sitemap generating , don’t know how many pages are cowling.

And I am generate site map using below tools online generate sitemap.

https://www.xml-sitemaps.com/ -> Total page : 36

http://www.web-site-map.com -> Total page : 324

All sitemap getting different result , can any one explain why it’s happening like this.

Thanks,

https://wordpress.org/plugins/google-sitemap-generator/