Twig template breaks when adding blocks Here's the issue:

I have a custom content type for the contact page. Twig template: page--node--9.html.twig. When I add blocks to this template, e.g. {{ page.contact-first }}, it breaks. How can I display blocks on it?
The solution was simple: the naming of the regions need to use underscores, not dashes.

In theme.info.yml

regions:
  contact_first: 'Contact (First column)'


In the twig template:

{{ page.contact_first }}