REST API curl error 28 Fix

I am using Newsever theme and get constantly REST API curl error 28 in Site Health.

What solved the issue was adding this to theme’s functions.php

add_action('init', function(){
    session_start(); //this loads variables to $_SESSION for reading
    if( empty($your_plugin_needs_session_saving) ){
        session_write_close(); //other plugins can restart a session again via session_start()
    } // if session writing is needed, close session after writing is done
});