I cannot change the static “Homepage” to others that I set initially. If I set to another one, the initially set page appears. I deleted this page, but still appears that one. Annoying!!!
If I change to another theme, the Homepage appears well…
The provided URL does not appear to be functional at this time. Do you use any form of caching? This can interfere with option changes.
I also notice the provided URL is a subfolder on an existing site. If the existing site has rewrite rules in place, these can also apply to the WordPress subfolder if they accidentally match, resulting in being displayed or getting redirected to incorrect site sections.