Big Cat Coins, Zeny, and Premium are not automatically added to the game after you make the purchase. You have to claim them first at the in-game mail. Here's how you can claim them.
1. Tap on the Mail icon located on the game homepage.
2. Click on the "Collect" button to claim the Coins, Zeny, or Premium into your game account.
The maximum limit for purchasing Premium is three times per month per account. If you exceed this limit, any additional purchases will automatically be converted into Big Cat Coins.