This plugin does not update my posts on sitemap.xml

I installed this plugin some years ago, but never looked at it since.

I just checked my /sitemap.xml and the last changes are shown as 2nd April 2014.

All listed pages and posts are dated between 19 September 2010 and 2nd April 2014.
None of my pages since then are showing.

My home page is shown Last modified 25 Mar 2014, even though it has been modified/updated at least 6 times since that date.

I am wondering if it is actually working now.

https://ww.wp.xz.cn/plugins/google-sitemap-generator/