The LiteSpeed web server sometimes has issues with scheduled WordPress tasks that take more than a short time – including all backup plugins.
The LiteSpeed server terminates requests that exceed a specific time, e.g., 30 seconds. You can add the following rules to the .htaccess file to prevent Litespeed timeouts:
RewriteEngine On
RewriteRule .*-[E=noabort:1, E=noconntimeout:1]
After doing that, check if the scheduled backups work.
If the above does not help, use WordPress’s alternative scheduling system and add the line below to your wp-config.php file:
define('ALTERNATE_WP_CRON', true);
If that doesn’t fix it, you’ll need the help of your web hosting company to figure out why the WordPress scheduler isn’t working on setup or is terminating prematurely. Otherwise, you will need another web hosting company. This issue is general and affects all backup plugins on WordPress that run through the scheduler (which all are, as far as we know).