Bug adventura Dr Boom

I’m doing the Dr. Boom adventure, and I found an error in Cabummestre in puzzle 2, where I must kill minions and receive mana, but it’s not happening, making it impossible to pass the challenge and complete it, there is a card in which each minion killed you get 1 mana, but killing 3 minions and having 1 mana, you only get 2 mana crystals, and all the other spells are 4 making it impossible to win and complete the mission.