The steps below should unlock your game again, as long as you're using the same Apple ID.
- Make sure you have a stable internet connection and tap the "restore purchase" button in the game, located in the game main menu. The game should then unlock and you’ll be able to play all levels.
- If you just made the purchase in the past 1-2 hours, make sure the transaction has been completed. You can check your purchase history to see if the purchase has been completed. If not, then try the purchase again. Open your purchase history by following these steps: http://support.apple.com/kb/ht2727
- Make sure you have purchased the item using the Apple ID you are logged in with. To see if this is the case, check you purchase history to see if the purchase is listed. If not, then make sure you are logged in with the correct Apple ID. Open your purchase history by following these steps: http://support.apple.com/kb/ht2727
Please note: you can always go through the purchasing process again, as long as you're using the same Apple ID (email address) that you used to purchase the game. You will not be charged twice, but should receive a message that you already own the game and the levels should be unlocked.