Where can you set up the quantity zero alert warning percentage?

1. You need to click on the Preferences > Advance

2. Based on the above image, you can set the warning halt process message percentage for the quantity of the product set to zero. This image is showing the Halt process when 30% of products' is set to zero.

3.  Once the threshold selected above is reached, the update will stop, and a warning message is displayed.

4. This warning message will show up in feed details when it affects the percentage you set it up of the inventory set to zero with the update that is mapped with the quantity field.

5. Stock Sync will stop the update process so that all your products won't be set to zero.

To continue update without warning, increase the limit higher or 100%. So, it will continue to update the inventory. 

6. To view the warning message info in the dashboard, can refer to the article here.  

You also can enable the notification option for this warning message

Preferences > Notifications > Quantity zero alert