Whenever I kill this npc, it won't give me exp. I think something is wrong with my weapon?.

So, I'm a pretty new scripter and im making a script where the player kills an npc, he or she gains Exp and that exp can used to lvl up and unlock new fighting styles which hit more and harder, I feel like the problem is my weapon because it is a combat weapon that has fighting moves and animations and all that a combat system has, how would I make this script work for the player so when they kill the npc, they gain Exp