Sitemap not updating for Q&A Lite

I have a site https://www.perftesting.co.uk and I have successfully installed Q&A Lite.
It appears to be working – however, the questions (i.e. posts) are not appearing in my sitemap.

The question:
https://www.perftesting.co.uk/questions/failover-testing-and-volume-testing-using-loadrunner/

Does not appear in my sitemap:
https://www.perftesting.co.uk/sitemap.xml

….I have updated my sitemap manually. Can anyone shed any light on this?

https://www.ads-software.com/extend/plugins/qa/