Cache cleaning via commands doesn’t work!

Hi there,

I’m trying to make cache scheduled cleaning using the shared server provider’s scheduler and info from W3TC FAQ showed below:

How can I flush the cache without using the WP Admin interface?

It’s possible to empty the entire cache or simply purge the cache of a single post / page:

Purge the entire cache of html content:
if (function_exists(‘w3tc_flush_posts’)) {
w3tc_flush_posts();
}
Purge a single post / page by passing it’s ID:
if (function_exists(‘w3tc_flush_post’)) {
w3tc_flush_post($post_id);
}

When I test it – it shows the message “Success”, but actually it does nothing, all files in cache remain as it was before launching command.

Please provide me info what I should adjust or what could be wrong in this settings. Thank you!