🤦♂️ That's frustrating but certainly can happen from time to time. Luckily, it's possible to easily solve this problem.
If you're on iOS, please visit the game's Settings which are accessible from the Main Menu. There you will find a "Restore Earlier Purchase..." option. Tap that and enter the same credentials you used when you made your original purchase. As long as you're using the same Apple ID, your earlier purchase will be restored at no cost.
On Android, simply visit your device's general settings and make sure you are signed into the same Google Play Services account you used when you made your original purchase. The next time you launch the app, your earlier purchase should restore automatically.