I can´t publish the title of my contact form
The page title is in a block, you most likely just need to add that to one of your theme's regions (or create a new region for it).

You can place the block through the settings link visiting Admin -> Structure -> Block Layout.

If you need to add a region, define it in your theme's .info.yml file:

regions:
  ...
  page_title: 'Page title'
  ...


And add it to your theme's page.html.twig template wherever you'd like it to render:

{{ page.page_title }}


Flush the cache, and visit the Block layout page again to place the block in your new region.