Automatic synchronization will keep Elastic and App Search up-to-date when data changes are made in the SmarterCommerce modules. If auto-synchronization is disabled, you must manually rebuild the index for the catalog and products after changes are made. Until synchronization occurs (either automatic or manual) your changes will be at the Sitefinity level only.  This may cause an issue where you see changes/updates in the Sitefinity backend, but you do not see them on the website frontend.