There's only a few reasons why one of your sales from an integrated platform may not be showing up, and it's simple to check for all of them.
Has your integration synced?
Check the time that your item sold and when the last sync was in Scout. If the item was sold after your most recent integration update, then Scout hasn't had a chance to detect and import the new sale. You can either wait for Scout to automatically sync, or click sync now to get it going immediately.
Is the item that sold sitting in your deleted section?
If your item syncs before the time of the sale, and you deleted it, it's probably sitting in the deleted section of your inventory. When items are there, they won't get updated if they sell and won't show up in your sales tab.
To see if it is there first go to your inventory and switch to the deleted status. Next, search for your item.
Once you find the item, right click it (or select it and click actions) and restore the item.
After doing so, you'll have to make sure your account syncs again to mark the item sold. If you still haven't been able to figure out why your sale isn't there, feel free to open a ticket through the Scout website and we'll help you find out what's happening!