Once on the WordPress health page (Tools – Website Health) I noticed several errors for the REST API and the Loopback request:
article Error:  cURL error 28: Operation timed out after 10000 milliseconds with 0 bytes received
In my case, the access was blocked by the “WP Limit Login Attempts” plugin that displays the captcha when logging in to the site, after disabling the plugin, the error disappeared.
same problem. the access was blocked by the “WP Limit Login Attempts”