You get to this page, it indicates that you have asked a recurrent question to support and that the answer is here;
1) “Profiles” tab no longer appears;
It is normal to make usage easy to neophytes, creating products has been made optional, leaving the time to the user to become familiar with the module. The Product Creation checkbox is available in Features tab, once selected, Profiles tab will appear.
2) Amazon sub-tab disappeared from the product sheet:
No, the tab has not disappeared but has been moved, now it is a native PrestaShop tab;
3) Order status changes or tracking number are no longer sent to Amazon
The workflow between v3.9 and 4.x changed. Now, statuses and tracking numbers are sent in batches through scheduled tasks. Sending single status changes has been removed to prevent API overuse; to preserve your API quotas.
Notifications are now sent periodically per scheduled task, please see Order Statuses page for more details about it.
4) “Marketplace” tabs for USA or Europe no longer appear;
You have to select Europe or Worldwide option in Features tab ;
