Love the game, but needs to fix bugs.

I LOVE THE GAME!!! Its awesome to play in my spare time. However, I recently ran out of energy so if I wait, I would get more energy. However, I waited for about 2 hours and it still left me with 3 energy instead of the 100 ish energy I was expecting. Please fix this. But other than that, I love the game

about The Battle Cats, v5.1.1