If you notice that your topping shelf has disappeared, please don't worry. It is probably "hidden" somewhere behind the items which stay close to your cafe walls.
You need to push off the walls all the items which are standing there, and the missing topping shelf will be found!
If you haven't found the topping shelf after that, please contact our technical support team. Our agents will be happy to help you. You can contact the support team from the game if you go to the following menu: Settings -> Support -> Help.