If you want to purchase an item and you don’t have enough coins, you are able to do this directly from the shop page.
Tap the item that you want to purchase with coins and confirm you want to buy it.
If you have enough coins, the item will be purchased instantly.
If you do not have enough coins, you will be prompted to convert some of the diamonds that you have to coins.
If you do not have enough diamonds or coins, you will be prompted to buy diamonds.
Diamond to coin conversion is no longer available in the Gift Shop.