Sorry, my mistake, it should apparently work with html files (read: [SOLVED] Using HTML for content pages instead of Markdown).
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 )