The REST API is one way WordPress, and other applications, communicate with the server. One example is the block editor screen, which relies on this to display, and save, your posts and pages.
The REST API request failed due to an error.
Error:  cURL error 28: Connection timed out after 10004 milliseconds
Loopback requests are used to run scheduled events, and are also used by the built-in editors for themes and plugins to verify code stability.
The loopback request to your site failed, this means features relying on them are not currently working as expected.
Error encountered: (0) cURL error 28: Connection timed out after 10003 milliseconds
i have tried all the methods like disabling all the plugins, stopping firewall, etc but still this error is not resolving.