If you accidentally delete an important item, like a Tool Barrel, and can't continue without it, check the Flash Sales in the Shop to see if the item is available there. 

 

If you accidentally sell an item, an "undo" button will be available for a limited time after selling it. Tapping this will return the item to you and remove the Coins you gained from the sale. This option is only available for the last item you've sold.

 

For missing or lost items, you can always send us a message with the "Contact Us" button in the top right corner of the screen.