Verify permission

First check Settings → Optional online diagnostics and make sure the switch is enabled and saved.

Outbound connections

Firewalls, security plugins, or hosting policies can block connections to WordPress.org. DNS functions can also be disabled at server level.

Self-tests

REST or loopback tests can be affected by Basic Auth, maintenance rules, security headers, web application firewalls, or blocked internal HTTP requests.

Consider caches

Several results are cached for periods ranging from 15 minutes to 24 hours. After fundamental changes, a new online result may therefore appear only after the relevant cache window expires or is cleared.