I think it’s because you seem to have html files under your content. Try it with a markdown file instead (i.e. _index.md, services.md etc) and see if the problem persists.
Do you have draft = false in your frontmatter? (alternatively, run hugo server with the --buildDrafts flag)
Additional notes:
Not sure if the underscore in _services.html is a typo or intentional, but that should render to /_services, not /services (see: Content organization | Hugo )
Note: It works if renaming _services.html to services.html, but then the browser is redirected to “services/”. It needs to as a page, without “/” at the end.
Your content files have .html extensions, but inside they are formatted as typical markdown files, which is odd.
You can have a markdown file with frontmatter, and, put html in it mixed with markdown, no problem. So why not try renaming your content files as .md instead.
Note that, you can indeed put “pure” html files in your /static folder, which gets served at the root of your site. That means, /static/path/to/myfile.html is served as http://mysite.com/path/to/myfile.html. In that case hugo won’t process them and just copy them into the site as appropriate, like it would with any other asset like a javascript or image file, under /static.