I was running low on time and activated "Narset's Rebuke" during Combat and was attempting to then play "Alesha's Legacy" when I did so, it stayed on top of the stack and the rest of the turn proceeded. Going into my opponents following turn and my next turn it was still visibly on the stack. I click on it and it spends it as if I casted it without letting me undo or take it back. This resulted in me losing the game and getting my third loss in the Draft Event. This is ridiculous.