Here is a checklist you can use to troubleshoot a missing item:

• Has the item been released in Commerce 365?
• What value is set for the Status field? This should be set to Enabled. When set to Disabled, an item can never be found on the Magento front-end.
• What value is set for the Visibility setting for this item? When set as Not visible individually, an item will only be shown as part of another item (grouped / configurable), but not on its own. 
• Is the item out-of-stock? When the inventory value is 0, the item is marked as out-of-stock, and will not be shown on the front end. Enable backorders to make out-of-stock items visible.
• If you have checked all of the above, and you believe that everything is set as it should, but items are still not visible, then the reason probably is a configuration error. Please contact your Magento developer to discuss the more technical checklist below.
   

Technical reasons for items not being shown on the Magento front-end:

• Configuration of caching. If caches are not updated because of missing configuration or missing cron jobs, then you might be looking at old information. 
• Configuration of indexing. If indexes are not updated because of missing configuration or missing cron jobs, you also might be looking at old information for a too long period of time. 
• Technical errors in 3rd party Magento modules. Modules that affect product listings which are throwing errors might also prevent items from being displayed in the front-end.