Hello Kesenia,

Thank you for reaching out, and I am happy to help!
Since the issue occurs randomly, it seems that the possible issue is related to your server configuration or resources, and when clearing the W3 Total Cache, the issue is fixed.

Enable logging in wp-config.php:

define(‘WP_DEBUG’, true);
define(‘WP_DEBUG_LOG’, true);
define(‘WP_DEBUG_DISPLAY’, false);

Then wait until the issue happens again and check:

/wp-content/debug.log
What can also be related to your hosting is:
– limit PHP workers
– kill long requests
-restart PHP-FPM automatically
-restart OPcache on deploys/backups

When that restart hits during a request – empty response.

Without cache, one visitor sees an error.
With cache – whole site blank.

Check if therea re any errors when the issue occurs.
Please let me know if you made any updates on your server, like changing the php version?
Also pelase check your PHP Memory Limit and let me know what is it

Thanks!