Note: This feature is only available on Gold and Platinum plans.
To enable auto-restock:
Go to Settings > Refunds & exchanges
In the Refunds & exchanges page, scroll down to Additional actions within the Refund within the app section.
Select the Auto-restock products check box to enable auto-restock. By switching this feature on your inventory will restock in Shopify automatically.
Select the Save button to save any changes made.
This feature is now enabled. When you're processing customers refund through the app, you can select the Restock item check box, if you would like to restock item.