Home page declares no Organization or WebSite entity
What this means
The site root carries no Organization or WebSite JSON-LD. These are the two entities search engines use to attach a name, logo and social profiles to the site as a whole, and WebSite is the prerequisite for a sitelinks search box. Every other page's markup describes a page; this is the one place the site itself gets described.
How to fix it
Add an Organization block (name, url, logo, sameAs links to your official profiles) and a WebSite block (name, url) to the home page — a single @graph containing both is the tidiest form.
Fix effort
This check needs review: the change can be drafted for you, but a person has to approve the wording or choose the target before it ships.
Authoritative source
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