Hi, there shouldn’t be any mistake, but right now I cannot check if it’s a bug or something else. Does it work for other user levels?
There are a lot of enforced exclusions, regardless of the setting.
Auto-saving (DOING_AUTOSAVE)
Installing WordPress (WP_INSTALLING)
Repairing WordPress (WP_REPAIRING)
Importing data (WP_IMPORTING)
Ajax requests (DOING_AJAX)
Command-line requests (WP_CLI)
XML-RPC requests (XMLRPC_REQUEST)
WordPress admin tasks (WP_ADMIN)
Short initialization (SHORTINIT)
IFrame requests (IFRAME_REQUEST)
REST API requests (REST_REQUEST)
404 Error pages (is_404)
Feeds (is_feed, is_comment_feed)
Attachment pages (is_attachment)
Trackbacks (is_trackback)
Robot.txt (is_robots)
Preview pages (is_preview, is_customize_preview)
Embeds (is_embed)
Admin pages (is_admin, is_blog_admin, is_network_admin)
Checkout pages (is_checkout)
Account pages (is_account_page)
WooCommerce Ajax (is_ajax)
WooCommerce endpoints (is_wc_endpoint_url)
certain static files, such as .txt, .xml, .xsl, .map, .css, .js, .png, .jpeg, .jpg, .gif, .webp, .ico, .php, .htaccess, .json, .pdf, .mp4, .webm.
Request must be a GET request and the requested domain must match the one on the wp_options.
Request cannot be an AMP page.
Request cannot have query strings, unless you specify them.
A possible case is the existence of some cookie that forces you to bypass cache, or in some cases caching (like OPCaching). If not, it might be a bug on the plugin. I will check in the near future if it’s the case.
Thanks