When retrieving dynamic fragments of a SmartCache page, if the origin returns an error code other than 200 or if they do not correspond to the locations setup on the page, the page is reloaded without SmartCache with the parameters :
frz-reason=invalid_status_code : return code of origin other than 200,
frz-reason=missing_fragments : fragments missing from locations in cached page,
frz-reason=missing_placeholder : some fragments do not match a location in the cached page.
We redirect the user to this page to avoid any cache problem on your site and to allow him to continue his navigation if it is possible. In the case of missing_fragments or missing_placeholder, contact our support with this information to verify or correct the SmartCache configuration.