Yes. Just cut the brown/black part of the leaf off and dab the cut with cinnamon. I use a Qtip for that. Why are you watering twice a week? That seems like a lot and that is probably the cause of this bacterial brown spot (acidovorax). Don't water overhead as this spreads the problem. It is rarely fatal but will eventually kill the leaf as it slowly enlarges. It primarily attacks older leaves. Just cut off that portion of the leaf and treat with cinnamon.