Rest API Error (cURL 28)

Hello there,

Recently I have noticed an error in the Site Health section. It’s the first time I am having such an error. I spent a couple of nights on this error but can not find a solution.

For a long time, I have been using the same set of plugins. But recently wanted to test some other caching plugins rather than my default Cache Enabler plugin. I tried LiteSpeed Cache, then gave up. My first thought was maybe it was because of this plugin change, but when I asked them, they confirmed that they didn’t have any injected left-over code for settings.

The REST API encountered an error
Performance
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 10000 milliseconds (http_request_failed)

Your site could not complete a loopback request
Performance
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: cURL error 28: Connection timed out after 10001 milliseconds (http_request_failed)

I also installed Query Monitor and checked it on the Site Health page and have these results below.

I mean I’m pretty technical in comparison to a beginner WP user but this is still taking me ages to figure out what’s happening. There were even people recommending a new website install which must be a joke as it’s a live site with many active visitors.

Wouldn’t it be better if Site Health could really point an issue for inspection rather than just giving us regular users a general statement?

GET	https://cigilovic.com/wp-json/wp/v2/types/post
?context=edit	cURL error 28: Connection timed out after 10000 milliseconds
WP_Site_Health->get_test_rest_availability()
wp-admin/includes/class-wp-site-health.php:2031
WP_Site_Health->perform_test()
wp-admin/includes/class-wp-site-health.php:177
WP_Site_Health->enqueue_scripts()
wp-admin/includes/class-wp-site-health.php:122
do_action('admin_enqueue_scripts')
wp-includes/plugin.php:484

Can anyone support me in diagnosing this problem, please? Internet is full of people having the same problem, but none of the solutions worked for me.

Many thanks

Osman