Quick answer: "Updating failed" or "Publishing failed" in the block editor almost always means the WordPress REST API is blocked or returning an error. The editor relies on the REST API to save posts. Common causes are a security plugin, a firewall rule, an incorrect site URL, or a plugin conflict blocking the API.
Go to Tools > Site Health. If it reports that the REST API encountered an error, that is your problem. You can also visit yourdomain.com/wp-json/ - it should return JSON, not an error page.
Security plugins and server firewalls sometimes block REST API requests. Temporarily disable the security plugin or whitelist the REST API, and re-test saving a post.
A mismatch between the WordPress Address and Site Address, or a partly broken HTTPS setup, can break REST calls. Confirm both URLs match and use the correct https://.
Deactivate plugins one by one (or all at once) and test. If saving works with them off, reactivate until the error returns to find the culprit.
Is this a problem with my content?
No - the content is fine. The editor simply cannot reach the API to save it.
Can I still edit meanwhile?
The classic editor does not depend on the REST API the same way, so it can be a temporary workaround while you fix the cause.
On SoftSys managed WordPress hosting the platform and firewall are configured so the REST API works correctly, and our team can diagnose blocked requests for you.
