Troubleshooting

Nothing is output

• The template has no <head>. Automatic output goes where Craft puts head HTML. Templates that never output </head>, such as XML feeds, get nothing, by design. Use {{ craft.schemy.render() }} if you need it elsewhere.
• Output automatically is off, and the template doesn't call craft.schemy.render().
• The page called craft.schemy.disable(), perhaps in a layout or a partial.

The main entity is missing

• The section has no type set, and neither does the entry type or the entry.
• The entry's Schemy field is set to Disable.
• The page isn't an entry's own URL. On custom routes, Craft has no matched element, so tell Schemy which one to describe with craft.schemy.setElement().

A property is missing

Schemy leaves out properties that resolve to nothing, so a mapped field that's empty on this entry produces no property rather than an empty string. Also check:

• Template errors. A template that fails to render is skipped and logged as a warning that starts with Schemy couldn't render template. It never breaks the page. Check storage/logs/web-*.log.
• The field isn't in this entry's layout. The field dropdown marks handles that aren't in the current layout as not in this layout.
• Twig in entry values is off. On the per-entry field, {title} is output literally unless the field allows Twig.

Running alongside SEOmatic or another SEO plugin

Both plugins will output JSON-LD. That's valid, but search engines then see two descriptions of the same page. Turn off the other plugin's structured data, or turn off Schemy's identity and WebSite nodes and keep only its main entities.

The settings pages are read-only

allowAdminChanges is off in this environment. Schemy settings are project config: change them locally and deploy.