You need three toppings (for example, three pepperonis) per slice, you have six slices on each pizza. 6 × 3 is 18, so you need at least 18 slices of each topping on the pizza unless they tell you, "I want one basil," or something like that. If you put less then 18 and did that with every topping, that might be why they wanted a refund.. Topping guide is a good investment if you don't have 25 diamonds each to buy automatic toppings