Stock Syncing
To Sync our warehouse stock to each of your integrations there are several locations to check/make sure are checked.
This allows for finer tuning of what items should be synced, and not.
Per Item
First, ensure your items you want to sync to the marketplace are set to sync. This will NOT sync still if your marketplace is not set to stock sync, this just allows you to control per-item level syncing.
Go to the Inventory landing page select the item you want and go to Stock Settings in here, change Stock Sync to Yes to sync from the warehouse stock, and No to have no syncing.
This can be done in bulk too if you want all your inventory, or those with certain tags, etc. to have Stock Sync enabled/disabled.
From the Inventory landing page, filter the page accordingly and select all, or each individual item you want to change the setting for, with these selected open Select Bulk Action from the bottom bar and from the dropdown select Enable Stock Sync or Disable Stock Sync, then Submit Action.
So, say we have tagged your inventory 'Dropship' for any stock we do not keep on hand here, but instead you manage. You would filter tags for Dropship, select all the items (maybe you'll need to adjust the amount shown per page, or go through each page), and Disable Stock Sync.
Marketplace Sync
On a per marketplace basis, edit the marketplace integration, go to the Stock Control tab, and check Auto Sync Stock to enable stock syncing, this will start a task to sync the stock levels.